diff --git a/src/Microsoft.AspNet.Mvc.Abstractions/ModelBinding/Validation/ValidationStateDictionary.cs b/src/Microsoft.AspNet.Mvc.Abstractions/ModelBinding/Validation/ValidationStateDictionary.cs
index 1a227692d7..99e1012f4d 100644
--- a/src/Microsoft.AspNet.Mvc.Abstractions/ModelBinding/Validation/ValidationStateDictionary.cs
+++ b/src/Microsoft.AspNet.Mvc.Abstractions/ModelBinding/Validation/ValidationStateDictionary.cs
@@ -163,6 +163,8 @@ namespace Microsoft.AspNet.Mvc.ModelBinding.Validation
         
         private class ReferenceEqualityComparer : IEqualityComparer<object>
         {
+            private static readonly bool IsMono = Type.GetType("Mono.Runtime") != null;
+
             public static readonly ReferenceEqualityComparer Instance = new ReferenceEqualityComparer();
 
             public new bool Equals(object x, object y)
@@ -172,6 +174,14 @@ namespace Microsoft.AspNet.Mvc.ModelBinding.Validation
 
             public int GetHashCode(object obj)
             {
+                // RuntimeHelpers.GetHashCode sometimes crashes the runtime on Mono 4.0.4
+                // See: https://github.com/aspnet/External/issues/45
+                // The workaround here is to just not hash anything, and fall back to an equality check.
+                if (IsMono)
+                {
+                    return 0;
+                }
+
                 return RuntimeHelpers.GetHashCode(obj);
             }
         }
diff --git a/src/Microsoft.AspNet.Mvc.Core/ModelBinding/Validation/DefaultComplexObjectValidationStrategy.cs b/src/Microsoft.AspNet.Mvc.Core/ModelBinding/Validation/DefaultComplexObjectValidationStrategy.cs
index 1e7205deed..6afc3ccdb5 100644
--- a/src/Microsoft.AspNet.Mvc.Core/ModelBinding/Validation/DefaultComplexObjectValidationStrategy.cs
+++ b/src/Microsoft.AspNet.Mvc.Core/ModelBinding/Validation/DefaultComplexObjectValidationStrategy.cs
@@ -4,6 +4,7 @@
 using System;
 using System.Collections;
 using System.Collections.Generic;
+using System.Reflection;
 
 namespace Microsoft.AspNet.Mvc.ModelBinding.Validation
 {
@@ -12,6 +13,8 @@ namespace Microsoft.AspNet.Mvc.ModelBinding.Validation
     /// </summary>
     public class DefaultComplexObjectValidationStrategy : IValidationStrategy
     {
+        private static readonly bool IsMono = Type.GetType("Mono.Runtime") != null;
+
         /// <summary>
         /// Gets an instance of <see cref="DefaultComplexObjectValidationStrategy"/>.
         /// </summary>
@@ -78,7 +81,34 @@ namespace Microsoft.AspNet.Mvc.ModelBinding.Validation
                 var property = _properties[_index];
                 var propertyName = property.BinderModelName ?? property.PropertyName;
                 var key = ModelNames.CreatePropertyModelName(_key, propertyName);
-                var model = property.PropertyGetter(_model);
+
+                object model;
+
+                // Our property accessors don't work on Mono 4.0.4 - see https://github.com/aspnet/External/issues/44
+                // This is a workaround for what the PropertyGetter does in the background.
+                if (IsMono)
+                {
+                    if (_model == null)
+                    {
+                        model = null;
+                    }
+                    else
+                    {
+                        var propertyInfo = _model.GetType().GetRuntimeProperty(property.PropertyName);
+                        try
+                        {
+                            model = propertyInfo.GetValue(_model);
+                        }
+                        catch (TargetInvocationException ex)
+                        {
+                            throw ex.InnerException;
+                        }
+                    }
+                }
+                else
+                {
+                    model = property.PropertyGetter(_model);
+                }
 
                 _entry = new ValidationEntry(property, key, model);
 
diff --git a/src/Microsoft.AspNet.Mvc.Core/ModelBinding/Validation/ReferenceEqualityComparer.cs b/src/Microsoft.AspNet.Mvc.Core/ModelBinding/Validation/ReferenceEqualityComparer.cs
index e1ab5ba427..ea6c2e2224 100644
--- a/src/Microsoft.AspNet.Mvc.Core/ModelBinding/Validation/ReferenceEqualityComparer.cs
+++ b/src/Microsoft.AspNet.Mvc.Core/ModelBinding/Validation/ReferenceEqualityComparer.cs
@@ -1,6 +1,7 @@
 // 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.Collections.Generic;
 using System.Runtime.CompilerServices;
 
@@ -10,6 +11,8 @@ namespace Microsoft.AspNet.Mvc.ModelBinding.Validation
     {
         private static readonly ReferenceEqualityComparer _instance = new ReferenceEqualityComparer();
 
+        private static readonly bool IsMono = Type.GetType("Mono.Runtime") != null;
+
         public static ReferenceEqualityComparer Instance
         {
             get
@@ -25,6 +28,14 @@ namespace Microsoft.AspNet.Mvc.ModelBinding.Validation
 
         public int GetHashCode(object obj)
         {
+            // RuntimeHelpers.GetHashCode sometimes crashes the runtime on Mono 4.0.4
+            // See: https://github.com/aspnet/External/issues/45
+            // The workaround here is to just not hash anything, and fall back to an equality check.
+            if (IsMono)
+            {
+                return 0;
+            }
+
             return RuntimeHelpers.GetHashCode(obj);
         }
     }