diff --git a/src/Microsoft.AspNetCore.Mvc.Razor.Extensions/MvcViewDocumentClassifierPass.cs b/src/Microsoft.AspNetCore.Mvc.Razor.Extensions/MvcViewDocumentClassifierPass.cs
index c2e99715c8..4341c8eec2 100644
--- a/src/Microsoft.AspNetCore.Mvc.Razor.Extensions/MvcViewDocumentClassifierPass.cs
+++ b/src/Microsoft.AspNetCore.Mvc.Razor.Extensions/MvcViewDocumentClassifierPass.cs
@@ -9,7 +9,7 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Extensions
 {
     public class MvcViewDocumentClassifierPass : DocumentClassifierPassBase
     {
-        public readonly string MvcViewDocumentKind = "mvc.1.0.view";
+        public static readonly string MvcViewDocumentKind = "mvc.1.0.view";
 
         protected override string DocumentKind => MvcViewDocumentKind;
 
diff --git a/src/Microsoft.AspNetCore.Mvc.Razor.Extensions/NamespaceDirective.cs b/src/Microsoft.AspNetCore.Mvc.Razor.Extensions/NamespaceDirective.cs
new file mode 100644
index 0000000000..188b60f6ca
--- /dev/null
+++ b/src/Microsoft.AspNetCore.Mvc.Razor.Extensions/NamespaceDirective.cs
@@ -0,0 +1,191 @@
+// Copyright (c) .NET Foundation. All rights reserved.
+// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
+
+using System;
+using System.IO;
+using System.Linq;
+using System.Text;
+using Microsoft.AspNetCore.Razor.Language;
+using Microsoft.AspNetCore.Razor.Language.Intermediate;
+
+namespace Microsoft.AspNetCore.Mvc.Razor.Extensions
+{
+    public static class NamespaceDirective
+    {
+        private static readonly char[] Separators = new char[] { '\\', '/' }; 
+
+        public static readonly DirectiveDescriptor Directive = DirectiveDescriptorBuilder.Create("namespace").AddNamespace().Build();
+
+        public static void Register(IRazorEngineBuilder builder)
+        {
+            if (builder == null)
+            {
+                throw new ArgumentNullException();
+            }
+
+            builder.AddDirective(Directive);
+            builder.Features.Add(new Pass());
+        }
+
+        // internal for testing
+        internal class Pass : RazorIRPassBase, IRazorDirectiveClassifierPass
+        {
+            public override void ExecuteCore(RazorCodeDocument codeDocument, DocumentIRNode irDocument)
+            {
+                if (irDocument.DocumentKind != RazorPageDocumentClassifierPass.RazorPageDocumentKind &&
+                    irDocument.DocumentKind != MvcViewDocumentClassifierPass.MvcViewDocumentKind)
+                {
+                    // Not a page. Skip.
+                    return;
+                }
+
+                var visitor = new Visitor();
+                visitor.Visit(irDocument);
+
+                var directive = visitor.LastNamespaceDirective;
+                if (directive == null)
+                {
+                    // No namespace set. Skip.
+                    return;
+                }
+
+                var @namespace = visitor.FirstNamespace;
+                if (@namespace == null)
+                {
+                    // No namespace node. Skip.
+                    return;
+                }
+                
+                if (TryComputeNamespace(codeDocument.Source.FileName, directive, out var computedNamespace))
+                {
+                    // Beautify the class name since we're using a hierarchy for namespaces.
+                    var @class = visitor.FirstClass;
+                    if (@class != null && irDocument.DocumentKind == RazorPageDocumentClassifierPass.RazorPageDocumentKind)
+                    {
+                        @class.Name = Path.GetFileNameWithoutExtension(codeDocument.Source.FileName) + "_Page";
+                    }
+                    else if (@class != null && irDocument.DocumentKind == MvcViewDocumentClassifierPass.MvcViewDocumentKind)
+                    {
+                        @class.Name = Path.GetFileNameWithoutExtension(codeDocument.Source.FileName) + "_View";
+                    }
+                }
+
+                @namespace.Content = computedNamespace;
+            }
+        }
+
+        // internal for testing.
+        //
+        // This code does a best-effort attempt to compute a namespace 'suffix' - the path difference between
+        // where the @namespace directive appears and where the current document is on disk.
+        //
+        // In the event that these two source either don't have filenames set or don't follow a coherent hierarchy,
+        // we will just use the namespace verbatim.
+        internal static bool TryComputeNamespace(string source, DirectiveIRNode directive, out string @namespace)
+        {
+            var directiveSource = NormalizeDirectory(directive.Source?.FilePath);
+
+            var baseNamespace = directive.Tokens.First().Content;
+            if (string.IsNullOrEmpty(source) || directiveSource == null)
+            {
+                // No sources, can't compute a suffix.
+                @namespace = baseNamespace;
+                return false;
+            }
+
+            // We're specifically using OrdinalIgnoreCase here because Razor treats all paths as case-insensitive.
+            if (!source.StartsWith(directiveSource, StringComparison.OrdinalIgnoreCase) ||
+                source.Length <= directiveSource.Length)
+            {
+                // The imports are not from the directory hierarchy, can't compute a suffix.
+                @namespace = baseNamespace;
+                return false;
+            }
+
+            // OK so that this point we know that the 'imports' file containing this directive is in the directory
+            // hierarchy of this soure file. This is the case where we can append a suffix to the baseNamespace.
+            //
+            // Everything so far has just been defensiveness on our part.
+
+            var builder = new StringBuilder(baseNamespace);
+
+            var segments = source.Substring(directiveSource.Length).Split(Separators);
+
+            // Skip the last segment because it's the filename.
+            for (var i = 0; i < segments.Length - 1; i++)
+            {
+                builder.Append('.');
+                builder.Append(segments[i]);
+            }
+
+            @namespace = builder.ToString();
+            return true;
+        }
+
+        // We want to normalize the path of the file containing the '@namespace' directive to just the containing
+        // directory with a trailing separator.
+        //
+        // Not using Path.GetDirectoryName here because it doesn't meet these requirements, and we want to handle
+        // both 'view engine' style paths and absolute paths.
+        //
+        // We also don't normalize the separators here. We expect that all documents are using a consistent style of path.
+        // 
+        // If we can't normalize the path, we just return null so it will be ignored.
+        private static string NormalizeDirectory(string path)
+        {
+            if (string.IsNullOrEmpty(path))
+            {
+                return null;
+            }
+
+            var lastSeparator = path.LastIndexOfAny(Separators);
+            if (lastSeparator == -1)
+            {
+                return null;
+            }
+
+            // Includes the separator
+            return path.Substring(0, lastSeparator + 1);
+        }
+
+        private class Visitor : RazorIRNodeWalker
+        {
+            public ClassDeclarationIRNode FirstClass { get; private set; }
+
+            public NamespaceDeclarationIRNode FirstNamespace { get; private set; }
+
+            // We want the last one, so get them all and then .
+            public DirectiveIRNode LastNamespaceDirective { get; private set; }
+
+            public override void VisitNamespace(NamespaceDeclarationIRNode node)
+            {
+                if (FirstNamespace == null)
+                {
+                    FirstNamespace = node;
+                }
+
+                base.VisitNamespace(node);
+            }
+
+            public override void VisitClass(ClassDeclarationIRNode node)
+            {
+                if (FirstClass == null)
+                {
+                    FirstClass = node;
+                }
+
+                base.VisitClass(node);
+            }
+
+            public override void VisitDirective(DirectiveIRNode node)
+            {
+                if (node.Descriptor == Directive)
+                {
+                    LastNamespaceDirective = node;
+                }
+
+                base.VisitDirective(node);
+            }
+        }
+    }
+}
diff --git a/src/Microsoft.AspNetCore.Mvc.Razor.Extensions/RazorExtensions.cs b/src/Microsoft.AspNetCore.Mvc.Razor.Extensions/RazorExtensions.cs
index edf39e5216..03bea5e656 100644
--- a/src/Microsoft.AspNetCore.Mvc.Razor.Extensions/RazorExtensions.cs
+++ b/src/Microsoft.AspNetCore.Mvc.Razor.Extensions/RazorExtensions.cs
@@ -11,6 +11,7 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Extensions
         {
             InjectDirective.Register(builder);
             ModelDirective.Register(builder);
+            NamespaceDirective.Register(builder);
             PageDirective.Register(builder);
 
             builder.AddTargetExtension(new InjectDirectiveTargetExtension());
diff --git a/src/Microsoft.AspNetCore.Razor.Language/Legacy/CSharpCodeParser.cs b/src/Microsoft.AspNetCore.Razor.Language/Legacy/CSharpCodeParser.cs
index 4e638e2249..d00d3570f1 100644
--- a/src/Microsoft.AspNetCore.Razor.Language/Legacy/CSharpCodeParser.cs
+++ b/src/Microsoft.AspNetCore.Razor.Language/Legacy/CSharpCodeParser.cs
@@ -110,6 +110,17 @@ namespace Microsoft.AspNetCore.Razor.Language.Legacy
             {
                 _directiveParsers.Add(directive, handler);
                 Keywords.Add(directive);
+
+                // These C# keywords are reserved for use in directives. It's an error to use them outside of
+                // a directive. This code removes the error generation if the directive *is* registered.
+                if (string.Equals(directive, "class", StringComparison.OrdinalIgnoreCase))
+                {
+                    _keywordParsers.Remove(CSharpKeyword.Class);
+                }
+                else if (string.Equals(directive, "namespace", StringComparison.OrdinalIgnoreCase))
+                {
+                    _keywordParsers.Remove(CSharpKeyword.Namespace);
+                }
             }
         }
 
@@ -266,8 +277,7 @@ namespace Microsoft.AspNetCore.Razor.Language.Legacy
                         }
                         else if (CurrentSymbol.Type == CSharpSymbolType.Identifier)
                         {
-                            Action handler;
-                            if (TryGetDirectiveHandler(CurrentSymbol.Content, out handler))
+                            if (TryGetDirectiveHandler(CurrentSymbol.Content, out var handler))
                             {
                                 Span.ChunkGenerator = SpanChunkGenerator.Null;
                                 handler();
@@ -295,8 +305,17 @@ namespace Microsoft.AspNetCore.Razor.Language.Legacy
                         }
                         else if (CurrentSymbol.Type == CSharpSymbolType.Keyword)
                         {
-                            KeywordBlock(topLevel: true);
-                            return;
+                            if (TryGetDirectiveHandler(CurrentSymbol.Content, out var handler))
+                            {
+                                Span.ChunkGenerator = SpanChunkGenerator.Null;
+                                handler();
+                                return;
+                            }
+                            else
+                            {
+                                KeywordBlock(topLevel: true);
+                                return;
+                            }
                         }
                         else if (CurrentSymbol.Type == CSharpSymbolType.LeftBrace)
                         {
@@ -737,7 +756,7 @@ namespace Microsoft.AspNetCore.Razor.Language.Legacy
             MapKeywords(TryStatement, CSharpKeyword.Try);
             MapKeywords(UsingKeyword, CSharpKeyword.Using);
             MapKeywords(DoStatement, CSharpKeyword.Do);
-            MapKeywords(ReservedDirective, CSharpKeyword.Namespace, CSharpKeyword.Class);
+            MapKeywords(ReservedDirective, CSharpKeyword.Class, CSharpKeyword.Namespace);
         }
 
         protected virtual void ReservedDirective(bool topLevel)
@@ -1748,7 +1767,7 @@ namespace Microsoft.AspNetCore.Razor.Language.Legacy
         [Conditional("DEBUG")]
         protected void AssertDirective(string directive)
         {
-            Assert(CSharpSymbolType.Identifier);
+            Debug.Assert(CurrentSymbol.Type == CSharpSymbolType.Identifier || CurrentSymbol.Type == CSharpSymbolType.Keyword);
             Debug.Assert(string.Equals(CurrentSymbol.Content, directive, StringComparison.Ordinal));
         }
 
diff --git a/test/Microsoft.AspNetCore.Mvc.Razor.Extensions.Test/IntegrationTests/CodeGenerationIntegrationTest.cs b/test/Microsoft.AspNetCore.Mvc.Razor.Extensions.Test/IntegrationTests/CodeGenerationIntegrationTest.cs
index bff7037e1d..779a691a3a 100644
--- a/test/Microsoft.AspNetCore.Mvc.Razor.Extensions.Test/IntegrationTests/CodeGenerationIntegrationTest.cs
+++ b/test/Microsoft.AspNetCore.Mvc.Razor.Extensions.Test/IntegrationTests/CodeGenerationIntegrationTest.cs
@@ -159,6 +159,36 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Extensions.IntegrationTests
             AssertIRMatchesBaseline(document.GetIRDocument());
             AssertCSharpDocumentMatchesBaseline(document.GetCSharpDocument());
         }
+
+        [Fact]
+        public void PageWithNamespace_Runtime()
+        {
+            // Arrange
+            var engine = CreateRuntimeEngine();
+            var document = CreateCodeDocument();
+
+            // Act
+            engine.Process(document);
+
+            // Assert
+            AssertIRMatchesBaseline(document.GetIRDocument());
+            AssertCSharpDocumentMatchesBaseline(document.GetCSharpDocument());
+        }
+
+        [Fact]
+        public void ViewWithNamespace_Runtime()
+        {
+            // Arrange
+            var engine = CreateRuntimeEngine();
+            var document = CreateCodeDocument();
+
+            // Act
+            engine.Process(document);
+
+            // Assert
+            AssertIRMatchesBaseline(document.GetIRDocument());
+            AssertCSharpDocumentMatchesBaseline(document.GetCSharpDocument());
+        }
         #endregion
 
         #region DesignTime
@@ -311,6 +341,36 @@ namespace Microsoft.AspNetCore.Mvc.Razor.Extensions.IntegrationTests
             AssertIRMatchesBaseline(document.GetIRDocument());
             AssertCSharpDocumentMatchesBaseline(document.GetCSharpDocument());
         }
+
+        [Fact]
+        public void PageWithNamespace_DesignTime()
+        {
+            // Arrange
+            var engine = CreateDesignTimeEngine();
+            var document = CreateCodeDocument();
+
+            // Act
+            engine.Process(document);
+
+            // Assert
+            AssertIRMatchesBaseline(document.GetIRDocument());
+            AssertCSharpDocumentMatchesBaseline(document.GetCSharpDocument());
+        }
+
+        [Fact]
+        public void ViewWithNamespace_DesignTime()
+        {
+            // Arrange
+            var engine = CreateDesignTimeEngine();
+            var document = CreateCodeDocument();
+
+            // Act
+            engine.Process(document);
+
+            // Assert
+            AssertIRMatchesBaseline(document.GetIRDocument());
+            AssertCSharpDocumentMatchesBaseline(document.GetCSharpDocument());
+        }
         #endregion
 
         protected RazorEngine CreateDesignTimeEngine(IEnumerable<TagHelperDescriptor> descriptors = null)
diff --git a/test/Microsoft.AspNetCore.Mvc.Razor.Extensions.Test/NamespaceDirectiveTest.cs b/test/Microsoft.AspNetCore.Mvc.Razor.Extensions.Test/NamespaceDirectiveTest.cs
new file mode 100644
index 0000000000..292afbd945
--- /dev/null
+++ b/test/Microsoft.AspNetCore.Mvc.Razor.Extensions.Test/NamespaceDirectiveTest.cs
@@ -0,0 +1,278 @@
+// Copyright (c) .NET Foundation. All rights reserved.
+// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
+
+using Microsoft.AspNetCore.Razor.Language;
+using Microsoft.AspNetCore.Razor.Language.Intermediate;
+using Xunit;
+
+namespace Microsoft.AspNetCore.Mvc.Razor.Extensions
+{
+    public class NamespaceDirectiveTest
+    {
+        // When we don't have a relationship between the source file and the imports file
+        // we will just use the namespace on the node directly.
+        [Theory]
+        [InlineData((string)null, (string)null)]
+        [InlineData("", "")]
+        [InlineData(null, "/foo/bar")]
+        [InlineData("/foo/baz", "/foo/bar/bleh")]
+        [InlineData("/foo.cshtml", "/foo/bar.cshtml")]
+        [InlineData("c:\\foo.cshtml", "d:\\foo\\bar.cshtml")]
+        [InlineData("c:\\foo\\bar\\bleh.cshtml", "c:\\foo\\baz\\bleh.cshtml")]
+        public void TryComputeNamespace_ForNonRelatedFiles_UsesNamespaceVerbatim(string source, string imports)
+        {
+            // Arrange
+            var node = new DirectiveIRNode()
+            {
+                Descriptor = NamespaceDirective.Directive,
+                Source = new SourceSpan(imports, 0, 0, 0, 0),
+            };
+
+            node.Children.Add(new DirectiveTokenIRNode() { Content = "Base" });
+            node.Children[0].Parent = node;
+
+            // Act
+            var computed = NamespaceDirective.TryComputeNamespace(source, node, out var @namespace);
+
+            // Assert
+            Assert.False(computed);
+            Assert.Equal("Base", @namespace);
+        }
+
+        [Theory]
+        [InlineData("/foo.cshtml", "/_ViewImports.cshtml", "Base")]
+        [InlineData("/foo/bar.cshtml", "/_ViewImports.cshtml", "Base.foo")]
+        [InlineData("/foo/bar/baz.cshtml", "/_ViewImports.cshtml", "Base.foo.bar")]
+        [InlineData("/foo/bar/baz.cshtml", "/foo/_ViewImports.cshtml", "Base.bar")]
+        [InlineData("/Foo/bar/baz.cshtml", "/foo/_ViewImports.cshtml", "Base.bar")]
+        [InlineData("c:\\foo.cshtml", "c:\\_ViewImports.cshtml", "Base")]
+        [InlineData("c:\\foo\\bar.cshtml", "c:\\_ViewImports.cshtml", "Base.foo")]
+        [InlineData("c:\\foo\\bar\\baz.cshtml", "c:\\_ViewImports.cshtml", "Base.foo.bar")]
+        [InlineData("c:\\foo\\bar\\baz.cshtml", "c:\\foo\\_ViewImports.cshtml", "Base.bar")]
+        [InlineData("c:\\Foo\\bar\\baz.cshtml", "c:\\foo\\_ViewImports.cshtml", "Base.bar")]
+        public void TryComputeNamespace_ForRelatedFiles_ComputesNamespaceWithSuffix(string source, string imports, string expected)
+        {
+            // Arrange
+            var node = new DirectiveIRNode()
+            {
+                Descriptor = NamespaceDirective.Directive,
+                Source = new SourceSpan(imports, 0, 0, 0, 0),
+            };
+
+            node.Children.Add(new DirectiveTokenIRNode() { Content = "Base" });
+            node.Children[0].Parent = node;
+
+            // Act
+            var computed = NamespaceDirective.TryComputeNamespace(source, node, out var @namespace);
+
+            // Assert
+            Assert.True(computed);
+            Assert.Equal(expected, @namespace);
+        }
+
+        // This is the case where a _ViewImports sets the namespace.
+        [Fact]
+        public void Pass_SetsNamespaceAndClassName_ComputedFromImports()
+        {
+            // Arrange
+            var builder = RazorIRBuilder.Document();
+
+            builder.Push(new DirectiveIRNode()
+            {
+                Descriptor = NamespaceDirective.Directive,
+                Source = new SourceSpan("/Account/_ViewImports.cshtml", 0, 0, 0, 0),
+            });
+            builder.Add(new DirectiveTokenIRNode() { Content = "WebApplication.Account" });
+            builder.Pop();
+
+            var @namespace = new NamespaceDeclarationIRNode() { Content = "default" };
+            builder.Push(@namespace);
+
+            var @class = new ClassDeclarationIRNode() { Name = "default" };
+            builder.Add(@class);
+
+            var irDocument = (DocumentIRNode)builder.Build();
+            irDocument.DocumentKind = RazorPageDocumentClassifierPass.RazorPageDocumentKind;
+
+            var codeDocument = RazorCodeDocument.Create(RazorSourceDocument.Create("ignored", "/Account/Manage/AddUser.cshtml"));
+
+            var pass = new NamespaceDirective.Pass();
+            pass.Engine = RazorEngine.CreateEmpty(b => { });
+
+            // Act
+            pass.Execute(codeDocument, irDocument);
+
+            // Assert
+            Assert.Equal("WebApplication.Account.Manage", @namespace.Content);
+            Assert.Equal("AddUser_Page", @class.Name);
+        }
+
+        // This is the case where the source file sets the namespace.
+        [Fact]
+        public void Pass_SetsNamespaceAndClassName_ComputedFromSource()
+        {
+            // Arrange
+            var builder = RazorIRBuilder.Document();
+
+            // This will be ignored.
+            builder.Push(new DirectiveIRNode()
+            {
+                Descriptor = NamespaceDirective.Directive,
+                Source = new SourceSpan("/Account/_ViewImports.cshtml", 0, 0, 0, 0),
+            });
+            builder.Add(new DirectiveTokenIRNode() { Content = "ignored" });
+            builder.Pop();
+
+            // This will be used.
+            builder.Push(new DirectiveIRNode()
+            {
+                Descriptor = NamespaceDirective.Directive,
+                Source = new SourceSpan("/Account/Manage/AddUser.cshtml", 0, 0, 0, 0),
+            });
+            builder.Add(new DirectiveTokenIRNode() { Content = "WebApplication.Account.Manage" });
+            builder.Pop();
+
+            var @namespace = new NamespaceDeclarationIRNode() { Content = "default" };
+            builder.Push(@namespace);
+
+            var @class = new ClassDeclarationIRNode() { Name = "default" };
+            builder.Add(@class);
+
+            var irDocument = (DocumentIRNode)builder.Build();
+            irDocument.DocumentKind = RazorPageDocumentClassifierPass.RazorPageDocumentKind;
+
+            var codeDocument = RazorCodeDocument.Create(RazorSourceDocument.Create("ignored", "/Account/Manage/AddUser.cshtml"));
+
+            var pass = new NamespaceDirective.Pass();
+            pass.Engine = RazorEngine.CreateEmpty(b => { });
+
+            // Act
+            pass.Execute(codeDocument, irDocument);
+
+            // Assert
+            Assert.Equal("WebApplication.Account.Manage", @namespace.Content);
+            Assert.Equal("AddUser_Page", @class.Name);
+        }
+
+        // This is the case where the source file sets the namespace.
+        [Fact]
+        public void Pass_SetsNamespaceAndClassName_ComputedFromSource_ForView()
+        {
+            // Arrange
+            var builder = RazorIRBuilder.Document();
+
+            // This will be ignored.
+            builder.Push(new DirectiveIRNode()
+            {
+                Descriptor = NamespaceDirective.Directive,
+                Source = new SourceSpan("/Account/_ViewImports.cshtml", 0, 0, 0, 0),
+            });
+            builder.Add(new DirectiveTokenIRNode() { Content = "ignored" });
+            builder.Pop();
+
+            // This will be used.
+            builder.Push(new DirectiveIRNode()
+            {
+                Descriptor = NamespaceDirective.Directive,
+                Source = new SourceSpan("/Account/Manage/AddUser.cshtml", 0, 0, 0, 0),
+            });
+            builder.Add(new DirectiveTokenIRNode() { Content = "WebApplication.Account.Manage" });
+            builder.Pop();
+
+            var @namespace = new NamespaceDeclarationIRNode() { Content = "default" };
+            builder.Push(@namespace);
+
+            var @class = new ClassDeclarationIRNode() { Name = "default" };
+            builder.Add(@class);
+
+            var irDocument = (DocumentIRNode)builder.Build();
+            irDocument.DocumentKind = MvcViewDocumentClassifierPass.MvcViewDocumentKind;
+
+            var codeDocument = RazorCodeDocument.Create(RazorSourceDocument.Create("ignored", "/Account/Manage/AddUser.cshtml"));
+
+            var pass = new NamespaceDirective.Pass();
+            pass.Engine = RazorEngine.CreateEmpty(b => { });
+
+            // Act
+            pass.Execute(codeDocument, irDocument);
+
+            // Assert
+            Assert.Equal("WebApplication.Account.Manage", @namespace.Content);
+            Assert.Equal("AddUser_View", @class.Name);
+        }
+
+        // This handles an error case where we can't determine the relationship between the
+        // imports and the source.
+        [Fact]
+        public void Pass_SetsNamespaceButNotClassName_VerbatimFromImports()
+        {
+            // Arrange
+            var builder = RazorIRBuilder.Document();
+
+            builder.Push(new DirectiveIRNode()
+            {
+                Descriptor = NamespaceDirective.Directive,
+                Source = new SourceSpan(null, 0, 0, 0, 0),
+            });
+            builder.Add(new DirectiveTokenIRNode() { Content = "WebApplication.Account" });
+            builder.Pop();
+
+            var @namespace = new NamespaceDeclarationIRNode() { Content = "default" };
+            builder.Push(@namespace);
+
+            var @class = new ClassDeclarationIRNode() { Name = "default" };
+            builder.Add(@class);
+
+            var irDocument = (DocumentIRNode)builder.Build();
+            irDocument.DocumentKind = RazorPageDocumentClassifierPass.RazorPageDocumentKind;
+
+            var codeDocument = RazorCodeDocument.Create(RazorSourceDocument.Create("ignored", "/Account/Manage/AddUser.cshtml"));
+
+            var pass = new NamespaceDirective.Pass();
+            pass.Engine = RazorEngine.CreateEmpty(b => { });
+
+            // Act
+            pass.Execute(codeDocument, irDocument);
+
+            // Assert
+            Assert.Equal("WebApplication.Account", @namespace.Content);
+            Assert.Equal("default", @class.Name);
+        }
+
+        [Fact]
+        public void Pass_DoesNothing_ForUnknownDocumentKind()
+        {
+            // Arrange
+            var builder = RazorIRBuilder.Document();
+
+            builder.Push(new DirectiveIRNode()
+            {
+                Descriptor = NamespaceDirective.Directive,
+                Source = new SourceSpan(null, 0, 0, 0, 0),
+            });
+            builder.Add(new DirectiveTokenIRNode() { Content = "WebApplication.Account" });
+            builder.Pop();
+
+            var @namespace = new NamespaceDeclarationIRNode() { Content = "default" };
+            builder.Push(@namespace);
+
+            var @class = new ClassDeclarationIRNode() { Name = "default" };
+            builder.Add(@class);
+
+            var irDocument = (DocumentIRNode)builder.Build();
+            irDocument.DocumentKind = null;
+
+            var codeDocument = RazorCodeDocument.Create(RazorSourceDocument.Create("ignored", "/Account/Manage/AddUser.cshtml"));
+
+            var pass = new NamespaceDirective.Pass();
+            pass.Engine = RazorEngine.CreateEmpty(b => { });
+
+            // Act
+            pass.Execute(codeDocument, irDocument);
+
+            // Assert
+            Assert.Equal("default", @namespace.Content);
+            Assert.Equal("default", @class.Name);
+        }
+    }
+}
diff --git a/test/Microsoft.AspNetCore.Mvc.Razor.Extensions.Test/TestFiles/IntegrationTests/CodeGenerationIntegrationTest/PageWithNamespace.cshtml b/test/Microsoft.AspNetCore.Mvc.Razor.Extensions.Test/TestFiles/IntegrationTests/CodeGenerationIntegrationTest/PageWithNamespace.cshtml
new file mode 100644
index 0000000000..ecee97de58
--- /dev/null
+++ b/test/Microsoft.AspNetCore.Mvc.Razor.Extensions.Test/TestFiles/IntegrationTests/CodeGenerationIntegrationTest/PageWithNamespace.cshtml
@@ -0,0 +1,3 @@
+@page
+@namespace Test.Namespace
+<h1>Hi There!</h1>
diff --git a/test/Microsoft.AspNetCore.Mvc.Razor.Extensions.Test/TestFiles/IntegrationTests/CodeGenerationIntegrationTest/PageWithNamespace_DesignTime.codegen.cs b/test/Microsoft.AspNetCore.Mvc.Razor.Extensions.Test/TestFiles/IntegrationTests/CodeGenerationIntegrationTest/PageWithNamespace_DesignTime.codegen.cs
new file mode 100644
index 0000000000..c8ba2ad454
--- /dev/null
+++ b/test/Microsoft.AspNetCore.Mvc.Razor.Extensions.Test/TestFiles/IntegrationTests/CodeGenerationIntegrationTest/PageWithNamespace_DesignTime.codegen.cs
@@ -0,0 +1,41 @@
+namespace Test.Namespace
+{
+    #line hidden
+    using TModel = PageWithNamespace_Page;
+    using System;
+    using System.Threading.Tasks;
+    using System.Linq;
+    using System.Collections.Generic;
+    using Microsoft.AspNetCore.Mvc;
+    using Microsoft.AspNetCore.Mvc.Rendering;
+    using Microsoft.AspNetCore.Mvc.ViewFeatures;
+    public class PageWithNamespace_Page : global::Microsoft.AspNetCore.Mvc.RazorPages.Page
+    {
+        #pragma warning disable 219
+        private void __RazorDirectiveTokenHelpers__() {
+        ((System.Action)(() => {
+global::System.Object __typeHelper = nameof(Test.Namespace);
+        }
+        ))();
+        }
+        #pragma warning restore 219
+        private static System.Object __o = null;
+        #pragma warning disable 1998
+        public async override global::System.Threading.Tasks.Task ExecuteAsync()
+        {
+        }
+        #pragma warning restore 1998
+        [global::Microsoft.AspNetCore.Mvc.Razor.Internal.RazorInjectAttribute]
+        public global::Microsoft.AspNetCore.Mvc.ViewFeatures.IModelExpressionProvider ModelExpressionProvider { get; private set; }
+        [global::Microsoft.AspNetCore.Mvc.Razor.Internal.RazorInjectAttribute]
+        public global::Microsoft.AspNetCore.Mvc.IUrlHelper Url { get; private set; }
+        [global::Microsoft.AspNetCore.Mvc.Razor.Internal.RazorInjectAttribute]
+        public global::Microsoft.AspNetCore.Mvc.IViewComponentHelper Component { get; private set; }
+        [global::Microsoft.AspNetCore.Mvc.Razor.Internal.RazorInjectAttribute]
+        public global::Microsoft.AspNetCore.Mvc.Rendering.IJsonHelper Json { get; private set; }
+        [global::Microsoft.AspNetCore.Mvc.Razor.Internal.RazorInjectAttribute]
+        public global::Microsoft.AspNetCore.Mvc.Rendering.IHtmlHelper<TestFiles_IntegrationTests_CodeGenerationIntegrationTest_PageWithNamespace_cshtml> Html { get; private set; }
+        public global::Microsoft.AspNetCore.Mvc.ViewFeatures.ViewDataDictionary<PageWithNamespace_Page> ViewData => (global::Microsoft.AspNetCore.Mvc.ViewFeatures.ViewDataDictionary<PageWithNamespace_Page>)PageContext?.ViewData;
+        public PageWithNamespace_Page Model => ViewData.Model;
+    }
+}
diff --git a/test/Microsoft.AspNetCore.Mvc.Razor.Extensions.Test/TestFiles/IntegrationTests/CodeGenerationIntegrationTest/PageWithNamespace_DesignTime.ir.txt b/test/Microsoft.AspNetCore.Mvc.Razor.Extensions.Test/TestFiles/IntegrationTests/CodeGenerationIntegrationTest/PageWithNamespace_DesignTime.ir.txt
new file mode 100644
index 0000000000..7007509973
--- /dev/null
+++ b/test/Microsoft.AspNetCore.Mvc.Razor.Extensions.Test/TestFiles/IntegrationTests/CodeGenerationIntegrationTest/PageWithNamespace_DesignTime.ir.txt
@@ -0,0 +1,52 @@
+Document - 
+    Checksum - 
+    NamespaceDeclaration -  - Test.Namespace
+        UsingStatement -  - TModel = PageWithNamespace_Page
+        UsingStatement - (1:0,1 [12] ) - System
+        UsingStatement -  - System.Threading.Tasks
+        UsingStatement - (16:1,1 [17] ) - System.Linq
+        UsingStatement - (36:2,1 [32] ) - System.Collections.Generic
+        UsingStatement - (71:3,1 [30] ) - Microsoft.AspNetCore.Mvc
+        UsingStatement - (104:4,1 [40] ) - Microsoft.AspNetCore.Mvc.Rendering
+        UsingStatement - (147:5,1 [43] ) - Microsoft.AspNetCore.Mvc.ViewFeatures
+        ClassDeclaration -  - public - PageWithNamespace_Page - global::Microsoft.AspNetCore.Mvc.RazorPages.Page - 
+            DirectiveTokenHelper - 
+                CSharpStatement - 
+                    RazorIRToken -  - CSharp - #pragma warning disable 219
+                CSharpStatement - 
+                    RazorIRToken -  - CSharp - private void __RazorDirectiveTokenHelpers__() {
+                DirectiveToken - (200:6,8 [62] ) - global::Microsoft.AspNetCore.Mvc.Rendering.IHtmlHelper<TModel>
+                DirectiveToken - (263:6,71 [4] ) - Html
+                DirectiveToken - (277:7,8 [54] ) - global::Microsoft.AspNetCore.Mvc.Rendering.IJsonHelper
+                DirectiveToken - (332:7,63 [4] ) - Json
+                DirectiveToken - (346:8,8 [53] ) - global::Microsoft.AspNetCore.Mvc.IViewComponentHelper
+                DirectiveToken - (400:8,62 [9] ) - Component
+                DirectiveToken - (419:9,8 [43] ) - global::Microsoft.AspNetCore.Mvc.IUrlHelper
+                DirectiveToken - (463:9,52 [3] ) - Url
+                DirectiveToken - (476:10,8 [70] ) - global::Microsoft.AspNetCore.Mvc.ViewFeatures.IModelExpressionProvider
+                DirectiveToken - (547:10,79 [23] ) - ModelExpressionProvider
+                DirectiveToken - (586:11,14 [96] ) - Microsoft.AspNetCore.Mvc.Razor.TagHelpers.UrlResolutionTagHelper, Microsoft.AspNetCore.Mvc.Razor
+                DirectiveToken - (698:12,14 [87] ) - Microsoft.AspNetCore.Mvc.Razor.TagHelpers.HeadTagHelper, Microsoft.AspNetCore.Mvc.Razor
+                DirectiveToken - (801:13,14 [87] ) - Microsoft.AspNetCore.Mvc.Razor.TagHelpers.BodyTagHelper, Microsoft.AspNetCore.Mvc.Razor
+                DirectiveToken - (18:1,11 [14] PageWithNamespace.cshtml) - Test.Namespace
+                CSharpStatement - 
+                    RazorIRToken -  - CSharp - }
+                CSharpStatement - 
+                    RazorIRToken -  - CSharp - #pragma warning restore 219
+            CSharpStatement - 
+                RazorIRToken -  - CSharp - private static System.Object __o = null;
+            RazorMethodDeclaration -  - public - async, override - global::System.Threading.Tasks.Task - ExecuteAsync
+                HtmlContent - (34:2,0 [20] PageWithNamespace.cshtml)
+                    RazorIRToken - (34:2,0 [4] PageWithNamespace.cshtml) - Html - <h1>
+                    RazorIRToken - (38:2,4 [9] PageWithNamespace.cshtml) - Html - Hi There!
+                    RazorIRToken - (47:2,13 [5] PageWithNamespace.cshtml) - Html - </h1>
+                    RazorIRToken - (52:2,18 [2] PageWithNamespace.cshtml) - Html - \n
+            InjectDirective - 
+            InjectDirective - 
+            InjectDirective - 
+            InjectDirective - 
+            InjectDirective - 
+            CSharpStatement - 
+                RazorIRToken -  - CSharp - public global::Microsoft.AspNetCore.Mvc.ViewFeatures.ViewDataDictionary<PageWithNamespace_Page> ViewData => (global::Microsoft.AspNetCore.Mvc.ViewFeatures.ViewDataDictionary<PageWithNamespace_Page>)PageContext?.ViewData;
+            CSharpStatement - 
+                RazorIRToken -  - CSharp - public PageWithNamespace_Page Model => ViewData.Model;
diff --git a/test/Microsoft.AspNetCore.Mvc.Razor.Extensions.Test/TestFiles/IntegrationTests/CodeGenerationIntegrationTest/PageWithNamespace_Runtime.codegen.cs b/test/Microsoft.AspNetCore.Mvc.Razor.Extensions.Test/TestFiles/IntegrationTests/CodeGenerationIntegrationTest/PageWithNamespace_Runtime.codegen.cs
new file mode 100644
index 0000000000..a8d2fad65c
--- /dev/null
+++ b/test/Microsoft.AspNetCore.Mvc.Razor.Extensions.Test/TestFiles/IntegrationTests/CodeGenerationIntegrationTest/PageWithNamespace_Runtime.codegen.cs
@@ -0,0 +1,35 @@
+#pragma checksum "TestFiles/IntegrationTests/CodeGenerationIntegrationTest/PageWithNamespace.cshtml" "{ff1816ec-aa5e-4d10-87f7-6f4963833460}" "b205857d3dad47cb3f0c1d7775ae251b306ab830"
+namespace Test.Namespace
+{
+    #line hidden
+    using System;
+    using System.Threading.Tasks;
+    using System.Linq;
+    using System.Collections.Generic;
+    using Microsoft.AspNetCore.Mvc;
+    using Microsoft.AspNetCore.Mvc.Rendering;
+    using Microsoft.AspNetCore.Mvc.ViewFeatures;
+    public class PageWithNamespace_Page : global::Microsoft.AspNetCore.Mvc.RazorPages.Page
+    {
+        #pragma warning disable 1998
+        public async override global::System.Threading.Tasks.Task ExecuteAsync()
+        {
+            BeginContext(34, 20, true);
+            WriteLiteral("<h1>Hi There!</h1>\r\n");
+            EndContext();
+        }
+        #pragma warning restore 1998
+        [global::Microsoft.AspNetCore.Mvc.Razor.Internal.RazorInjectAttribute]
+        public global::Microsoft.AspNetCore.Mvc.ViewFeatures.IModelExpressionProvider ModelExpressionProvider { get; private set; }
+        [global::Microsoft.AspNetCore.Mvc.Razor.Internal.RazorInjectAttribute]
+        public global::Microsoft.AspNetCore.Mvc.IUrlHelper Url { get; private set; }
+        [global::Microsoft.AspNetCore.Mvc.Razor.Internal.RazorInjectAttribute]
+        public global::Microsoft.AspNetCore.Mvc.IViewComponentHelper Component { get; private set; }
+        [global::Microsoft.AspNetCore.Mvc.Razor.Internal.RazorInjectAttribute]
+        public global::Microsoft.AspNetCore.Mvc.Rendering.IJsonHelper Json { get; private set; }
+        [global::Microsoft.AspNetCore.Mvc.Razor.Internal.RazorInjectAttribute]
+        public global::Microsoft.AspNetCore.Mvc.Rendering.IHtmlHelper<TestFiles_IntegrationTests_CodeGenerationIntegrationTest_PageWithNamespace_cshtml> Html { get; private set; }
+        public global::Microsoft.AspNetCore.Mvc.ViewFeatures.ViewDataDictionary<PageWithNamespace_Page> ViewData => (global::Microsoft.AspNetCore.Mvc.ViewFeatures.ViewDataDictionary<PageWithNamespace_Page>)PageContext?.ViewData;
+        public PageWithNamespace_Page Model => ViewData.Model;
+    }
+}
diff --git a/test/Microsoft.AspNetCore.Mvc.Razor.Extensions.Test/TestFiles/IntegrationTests/CodeGenerationIntegrationTest/PageWithNamespace_Runtime.ir.txt b/test/Microsoft.AspNetCore.Mvc.Razor.Extensions.Test/TestFiles/IntegrationTests/CodeGenerationIntegrationTest/PageWithNamespace_Runtime.ir.txt
new file mode 100644
index 0000000000..512d0daa1e
--- /dev/null
+++ b/test/Microsoft.AspNetCore.Mvc.Razor.Extensions.Test/TestFiles/IntegrationTests/CodeGenerationIntegrationTest/PageWithNamespace_Runtime.ir.txt
@@ -0,0 +1,30 @@
+Document - 
+    Checksum - 
+    NamespaceDeclaration -  - Test.Namespace
+        UsingStatement - (1:0,1 [14] ) - System
+        UsingStatement -  - System.Threading.Tasks
+        UsingStatement - (16:1,1 [19] ) - System.Linq
+        UsingStatement - (36:2,1 [34] ) - System.Collections.Generic
+        UsingStatement - (71:3,1 [32] ) - Microsoft.AspNetCore.Mvc
+        UsingStatement - (104:4,1 [42] ) - Microsoft.AspNetCore.Mvc.Rendering
+        UsingStatement - (147:5,1 [45] ) - Microsoft.AspNetCore.Mvc.ViewFeatures
+        ClassDeclaration -  - public - PageWithNamespace_Page - global::Microsoft.AspNetCore.Mvc.RazorPages.Page - 
+            RazorMethodDeclaration -  - public - async, override - global::System.Threading.Tasks.Task - ExecuteAsync
+                CSharpStatement - 
+                    RazorIRToken -  - CSharp - BeginContext(34, 20, true);
+                HtmlContent - (34:2,0 [20] PageWithNamespace.cshtml)
+                    RazorIRToken - (34:2,0 [4] PageWithNamespace.cshtml) - Html - <h1>
+                    RazorIRToken - (38:2,4 [9] PageWithNamespace.cshtml) - Html - Hi There!
+                    RazorIRToken - (47:2,13 [5] PageWithNamespace.cshtml) - Html - </h1>
+                    RazorIRToken - (52:2,18 [2] PageWithNamespace.cshtml) - Html - \n
+                CSharpStatement - 
+                    RazorIRToken -  - CSharp - EndContext();
+            InjectDirective - 
+            InjectDirective - 
+            InjectDirective - 
+            InjectDirective - 
+            InjectDirective - 
+            CSharpStatement - 
+                RazorIRToken -  - CSharp - public global::Microsoft.AspNetCore.Mvc.ViewFeatures.ViewDataDictionary<PageWithNamespace_Page> ViewData => (global::Microsoft.AspNetCore.Mvc.ViewFeatures.ViewDataDictionary<PageWithNamespace_Page>)PageContext?.ViewData;
+            CSharpStatement - 
+                RazorIRToken -  - CSharp - public PageWithNamespace_Page Model => ViewData.Model;
diff --git a/test/Microsoft.AspNetCore.Mvc.Razor.Extensions.Test/TestFiles/IntegrationTests/CodeGenerationIntegrationTest/ViewWithNamespace.cshtml b/test/Microsoft.AspNetCore.Mvc.Razor.Extensions.Test/TestFiles/IntegrationTests/CodeGenerationIntegrationTest/ViewWithNamespace.cshtml
new file mode 100644
index 0000000000..eaf33e48ec
--- /dev/null
+++ b/test/Microsoft.AspNetCore.Mvc.Razor.Extensions.Test/TestFiles/IntegrationTests/CodeGenerationIntegrationTest/ViewWithNamespace.cshtml
@@ -0,0 +1,2 @@
+@namespace Test.Namespace
+<h1>Hi There!</h1>
diff --git a/test/Microsoft.AspNetCore.Mvc.Razor.Extensions.Test/TestFiles/IntegrationTests/CodeGenerationIntegrationTest/ViewWithNamespace_DesignTime.codegen.cs b/test/Microsoft.AspNetCore.Mvc.Razor.Extensions.Test/TestFiles/IntegrationTests/CodeGenerationIntegrationTest/ViewWithNamespace_DesignTime.codegen.cs
new file mode 100644
index 0000000000..32ada4b8fd
--- /dev/null
+++ b/test/Microsoft.AspNetCore.Mvc.Razor.Extensions.Test/TestFiles/IntegrationTests/CodeGenerationIntegrationTest/ViewWithNamespace_DesignTime.codegen.cs
@@ -0,0 +1,39 @@
+namespace Test.Namespace
+{
+    #line hidden
+    using TModel = global::System.Object;
+    using System;
+    using System.Threading.Tasks;
+    using System.Linq;
+    using System.Collections.Generic;
+    using Microsoft.AspNetCore.Mvc;
+    using Microsoft.AspNetCore.Mvc.Rendering;
+    using Microsoft.AspNetCore.Mvc.ViewFeatures;
+    public class ViewWithNamespace_View : global::Microsoft.AspNetCore.Mvc.Razor.RazorPage<dynamic>
+    {
+        #pragma warning disable 219
+        private void __RazorDirectiveTokenHelpers__() {
+        ((System.Action)(() => {
+global::System.Object __typeHelper = nameof(Test.Namespace);
+        }
+        ))();
+        }
+        #pragma warning restore 219
+        private static System.Object __o = null;
+        #pragma warning disable 1998
+        public async override global::System.Threading.Tasks.Task ExecuteAsync()
+        {
+        }
+        #pragma warning restore 1998
+        [global::Microsoft.AspNetCore.Mvc.Razor.Internal.RazorInjectAttribute]
+        public global::Microsoft.AspNetCore.Mvc.ViewFeatures.IModelExpressionProvider ModelExpressionProvider { get; private set; }
+        [global::Microsoft.AspNetCore.Mvc.Razor.Internal.RazorInjectAttribute]
+        public global::Microsoft.AspNetCore.Mvc.IUrlHelper Url { get; private set; }
+        [global::Microsoft.AspNetCore.Mvc.Razor.Internal.RazorInjectAttribute]
+        public global::Microsoft.AspNetCore.Mvc.IViewComponentHelper Component { get; private set; }
+        [global::Microsoft.AspNetCore.Mvc.Razor.Internal.RazorInjectAttribute]
+        public global::Microsoft.AspNetCore.Mvc.Rendering.IJsonHelper Json { get; private set; }
+        [global::Microsoft.AspNetCore.Mvc.Razor.Internal.RazorInjectAttribute]
+        public global::Microsoft.AspNetCore.Mvc.Rendering.IHtmlHelper<dynamic> Html { get; private set; }
+    }
+}
diff --git a/test/Microsoft.AspNetCore.Mvc.Razor.Extensions.Test/TestFiles/IntegrationTests/CodeGenerationIntegrationTest/ViewWithNamespace_DesignTime.ir.txt b/test/Microsoft.AspNetCore.Mvc.Razor.Extensions.Test/TestFiles/IntegrationTests/CodeGenerationIntegrationTest/ViewWithNamespace_DesignTime.ir.txt
new file mode 100644
index 0000000000..e8cd81f770
--- /dev/null
+++ b/test/Microsoft.AspNetCore.Mvc.Razor.Extensions.Test/TestFiles/IntegrationTests/CodeGenerationIntegrationTest/ViewWithNamespace_DesignTime.ir.txt
@@ -0,0 +1,48 @@
+Document - 
+    Checksum - 
+    NamespaceDeclaration -  - Test.Namespace
+        UsingStatement -  - TModel = global::System.Object
+        UsingStatement - (1:0,1 [12] ) - System
+        UsingStatement -  - System.Threading.Tasks
+        UsingStatement - (16:1,1 [17] ) - System.Linq
+        UsingStatement - (36:2,1 [32] ) - System.Collections.Generic
+        UsingStatement - (71:3,1 [30] ) - Microsoft.AspNetCore.Mvc
+        UsingStatement - (104:4,1 [40] ) - Microsoft.AspNetCore.Mvc.Rendering
+        UsingStatement - (147:5,1 [43] ) - Microsoft.AspNetCore.Mvc.ViewFeatures
+        ClassDeclaration -  - public - ViewWithNamespace_View - global::Microsoft.AspNetCore.Mvc.Razor.RazorPage<dynamic> - 
+            DirectiveTokenHelper - 
+                CSharpStatement - 
+                    RazorIRToken -  - CSharp - #pragma warning disable 219
+                CSharpStatement - 
+                    RazorIRToken -  - CSharp - private void __RazorDirectiveTokenHelpers__() {
+                DirectiveToken - (200:6,8 [62] ) - global::Microsoft.AspNetCore.Mvc.Rendering.IHtmlHelper<TModel>
+                DirectiveToken - (263:6,71 [4] ) - Html
+                DirectiveToken - (277:7,8 [54] ) - global::Microsoft.AspNetCore.Mvc.Rendering.IJsonHelper
+                DirectiveToken - (332:7,63 [4] ) - Json
+                DirectiveToken - (346:8,8 [53] ) - global::Microsoft.AspNetCore.Mvc.IViewComponentHelper
+                DirectiveToken - (400:8,62 [9] ) - Component
+                DirectiveToken - (419:9,8 [43] ) - global::Microsoft.AspNetCore.Mvc.IUrlHelper
+                DirectiveToken - (463:9,52 [3] ) - Url
+                DirectiveToken - (476:10,8 [70] ) - global::Microsoft.AspNetCore.Mvc.ViewFeatures.IModelExpressionProvider
+                DirectiveToken - (547:10,79 [23] ) - ModelExpressionProvider
+                DirectiveToken - (586:11,14 [96] ) - Microsoft.AspNetCore.Mvc.Razor.TagHelpers.UrlResolutionTagHelper, Microsoft.AspNetCore.Mvc.Razor
+                DirectiveToken - (698:12,14 [87] ) - Microsoft.AspNetCore.Mvc.Razor.TagHelpers.HeadTagHelper, Microsoft.AspNetCore.Mvc.Razor
+                DirectiveToken - (801:13,14 [87] ) - Microsoft.AspNetCore.Mvc.Razor.TagHelpers.BodyTagHelper, Microsoft.AspNetCore.Mvc.Razor
+                DirectiveToken - (11:0,11 [14] ViewWithNamespace.cshtml) - Test.Namespace
+                CSharpStatement - 
+                    RazorIRToken -  - CSharp - }
+                CSharpStatement - 
+                    RazorIRToken -  - CSharp - #pragma warning restore 219
+            CSharpStatement - 
+                RazorIRToken -  - CSharp - private static System.Object __o = null;
+            RazorMethodDeclaration -  - public - async, override - global::System.Threading.Tasks.Task - ExecuteAsync
+                HtmlContent - (27:1,0 [20] ViewWithNamespace.cshtml)
+                    RazorIRToken - (27:1,0 [4] ViewWithNamespace.cshtml) - Html - <h1>
+                    RazorIRToken - (31:1,4 [9] ViewWithNamespace.cshtml) - Html - Hi There!
+                    RazorIRToken - (40:1,13 [5] ViewWithNamespace.cshtml) - Html - </h1>
+                    RazorIRToken - (45:1,18 [2] ViewWithNamespace.cshtml) - Html - \n
+            InjectDirective - 
+            InjectDirective - 
+            InjectDirective - 
+            InjectDirective - 
+            InjectDirective - 
diff --git a/test/Microsoft.AspNetCore.Mvc.Razor.Extensions.Test/TestFiles/IntegrationTests/CodeGenerationIntegrationTest/ViewWithNamespace_Runtime.codegen.cs b/test/Microsoft.AspNetCore.Mvc.Razor.Extensions.Test/TestFiles/IntegrationTests/CodeGenerationIntegrationTest/ViewWithNamespace_Runtime.codegen.cs
new file mode 100644
index 0000000000..f467c598d1
--- /dev/null
+++ b/test/Microsoft.AspNetCore.Mvc.Razor.Extensions.Test/TestFiles/IntegrationTests/CodeGenerationIntegrationTest/ViewWithNamespace_Runtime.codegen.cs
@@ -0,0 +1,33 @@
+#pragma checksum "TestFiles/IntegrationTests/CodeGenerationIntegrationTest/ViewWithNamespace.cshtml" "{ff1816ec-aa5e-4d10-87f7-6f4963833460}" "2893acf42354a0bc8b6a2698f5d2e4fab0e59dbe"
+namespace Test.Namespace
+{
+    #line hidden
+    using System;
+    using System.Threading.Tasks;
+    using System.Linq;
+    using System.Collections.Generic;
+    using Microsoft.AspNetCore.Mvc;
+    using Microsoft.AspNetCore.Mvc.Rendering;
+    using Microsoft.AspNetCore.Mvc.ViewFeatures;
+    public class ViewWithNamespace_View : global::Microsoft.AspNetCore.Mvc.Razor.RazorPage<dynamic>
+    {
+        #pragma warning disable 1998
+        public async override global::System.Threading.Tasks.Task ExecuteAsync()
+        {
+            BeginContext(27, 20, true);
+            WriteLiteral("<h1>Hi There!</h1>\r\n");
+            EndContext();
+        }
+        #pragma warning restore 1998
+        [global::Microsoft.AspNetCore.Mvc.Razor.Internal.RazorInjectAttribute]
+        public global::Microsoft.AspNetCore.Mvc.ViewFeatures.IModelExpressionProvider ModelExpressionProvider { get; private set; }
+        [global::Microsoft.AspNetCore.Mvc.Razor.Internal.RazorInjectAttribute]
+        public global::Microsoft.AspNetCore.Mvc.IUrlHelper Url { get; private set; }
+        [global::Microsoft.AspNetCore.Mvc.Razor.Internal.RazorInjectAttribute]
+        public global::Microsoft.AspNetCore.Mvc.IViewComponentHelper Component { get; private set; }
+        [global::Microsoft.AspNetCore.Mvc.Razor.Internal.RazorInjectAttribute]
+        public global::Microsoft.AspNetCore.Mvc.Rendering.IJsonHelper Json { get; private set; }
+        [global::Microsoft.AspNetCore.Mvc.Razor.Internal.RazorInjectAttribute]
+        public global::Microsoft.AspNetCore.Mvc.Rendering.IHtmlHelper<dynamic> Html { get; private set; }
+    }
+}
diff --git a/test/Microsoft.AspNetCore.Mvc.Razor.Extensions.Test/TestFiles/IntegrationTests/CodeGenerationIntegrationTest/ViewWithNamespace_Runtime.ir.txt b/test/Microsoft.AspNetCore.Mvc.Razor.Extensions.Test/TestFiles/IntegrationTests/CodeGenerationIntegrationTest/ViewWithNamespace_Runtime.ir.txt
new file mode 100644
index 0000000000..60e9a65d25
--- /dev/null
+++ b/test/Microsoft.AspNetCore.Mvc.Razor.Extensions.Test/TestFiles/IntegrationTests/CodeGenerationIntegrationTest/ViewWithNamespace_Runtime.ir.txt
@@ -0,0 +1,26 @@
+Document - 
+    Checksum - 
+    NamespaceDeclaration -  - Test.Namespace
+        UsingStatement - (1:0,1 [14] ) - System
+        UsingStatement -  - System.Threading.Tasks
+        UsingStatement - (16:1,1 [19] ) - System.Linq
+        UsingStatement - (36:2,1 [34] ) - System.Collections.Generic
+        UsingStatement - (71:3,1 [32] ) - Microsoft.AspNetCore.Mvc
+        UsingStatement - (104:4,1 [42] ) - Microsoft.AspNetCore.Mvc.Rendering
+        UsingStatement - (147:5,1 [45] ) - Microsoft.AspNetCore.Mvc.ViewFeatures
+        ClassDeclaration -  - public - ViewWithNamespace_View - global::Microsoft.AspNetCore.Mvc.Razor.RazorPage<dynamic> - 
+            RazorMethodDeclaration -  - public - async, override - global::System.Threading.Tasks.Task - ExecuteAsync
+                CSharpStatement - 
+                    RazorIRToken -  - CSharp - BeginContext(27, 20, true);
+                HtmlContent - (27:1,0 [20] ViewWithNamespace.cshtml)
+                    RazorIRToken - (27:1,0 [4] ViewWithNamespace.cshtml) - Html - <h1>
+                    RazorIRToken - (31:1,4 [9] ViewWithNamespace.cshtml) - Html - Hi There!
+                    RazorIRToken - (40:1,13 [5] ViewWithNamespace.cshtml) - Html - </h1>
+                    RazorIRToken - (45:1,18 [2] ViewWithNamespace.cshtml) - Html - \n
+                CSharpStatement - 
+                    RazorIRToken -  - CSharp - EndContext();
+            InjectDirective - 
+            InjectDirective - 
+            InjectDirective - 
+            InjectDirective - 
+            InjectDirective - 
diff --git a/test/Microsoft.AspNetCore.Razor.Language.Test/Legacy/CSharpDirectivesTest.cs b/test/Microsoft.AspNetCore.Razor.Language.Test/Legacy/CSharpDirectivesTest.cs
index 9bbe9030ff..e56b58b482 100644
--- a/test/Microsoft.AspNetCore.Razor.Language.Test/Legacy/CSharpDirectivesTest.cs
+++ b/test/Microsoft.AspNetCore.Razor.Language.Test/Legacy/CSharpDirectivesTest.cs
@@ -1017,6 +1017,39 @@ namespace Microsoft.AspNetCore.Razor.Language.Legacy
                         .With(new DirectiveTokenChunkGenerator(descriptor.Tokens.First()))));
         }
 
+        [Fact]
+        public void Directives_CanUseReservedWord_Class()
+        {
+            // Arrange
+            var descriptor = DirectiveDescriptorBuilder.Create("class").Build();
+
+            // Act & Assert
+            ParseCodeBlockTest(
+                "@class",
+                new[] { descriptor },
+                new DirectiveBlock(
+                    new DirectiveChunkGenerator(descriptor),
+                    Factory.CodeTransition(),
+                    Factory.MetaCode("class").Accepts(AcceptedCharacters.None)));
+        }
+
+        [Fact]
+        public void Directives_CanUseReservedWord_Namespace()
+        {
+            // Arrange
+            var descriptor = DirectiveDescriptorBuilder.Create("namespace").Build();
+
+            // Act & Assert
+            ParseCodeBlockTest(
+                "@namespace",
+                new[] { descriptor },
+                new DirectiveBlock(
+                    new DirectiveChunkGenerator(descriptor),
+                    Factory.CodeTransition(),
+                    Factory.MetaCode("namespace").Accepts(AcceptedCharacters.None)));
+        }
+
+
         internal virtual void ParseCodeBlockTest(
             string document,
             IEnumerable<DirectiveDescriptor> descriptors,