diff --git a/Slapper.AutoMapper.Tests/Slapper.Tests.csproj b/Slapper.AutoMapper.Tests/Slapper.Tests.csproj
index 78efd18..ebf2d37 100644
--- a/Slapper.AutoMapper.Tests/Slapper.Tests.csproj
+++ b/Slapper.AutoMapper.Tests/Slapper.Tests.csproj
@@ -80,6 +80,9 @@
   <ItemGroup>
     <Service Include="{82A7F48D-3B50-4B1E-B82E-3ADA8210C358}" />
   </ItemGroup>
+  <ItemGroup>
+    <None Include="packages.config" />
+  </ItemGroup>
   <Import Project="$(MSBuildToolsPath)\Microsoft.CSharp.targets" />
   <!-- To modify your build process, add your task inside one of the targets below and uncomment it. 
        Other similar extension points exist, see Microsoft.Common.targets.
diff --git a/Slapper.AutoMapper.Tests/packages.config b/Slapper.AutoMapper.Tests/packages.config
index 65459cd..d219c1d 100644
--- a/Slapper.AutoMapper.Tests/packages.config
+++ b/Slapper.AutoMapper.Tests/packages.config
@@ -1,4 +1,4 @@
 <?xml version="1.0" encoding="utf-8"?>
 <packages>
-  <package id="NUnitTestAdapter" version="2.0.0" targetFramework="net4" userInstalled="true" />
+  <package id="NUnitTestAdapter" version="2.1.1" targetFramework="net40" userInstalled="true" />
 </packages>
\ No newline at end of file
diff --git a/Slapper.AutoMapper/Slapper.AutoMapper.InternalHelpers.cs b/Slapper.AutoMapper/Slapper.AutoMapper.InternalHelpers.cs
index 55a6a5c..4bc7f65 100644
--- a/Slapper.AutoMapper/Slapper.AutoMapper.InternalHelpers.cs
+++ b/Slapper.AutoMapper/Slapper.AutoMapper.InternalHelpers.cs
@@ -33,6 +33,7 @@ dynamic data into static types and populate complex nested child objects.
 using System;
 using System.Collections;
 using System.Collections.Generic;
+using System.Globalization;
 using System.Linq;
 using System.Reflection;
 using System.Runtime.Remoting.Messaging;
@@ -49,6 +50,8 @@ public static partial class AutoMapper
         /// </summary>
         internal static class InternalHelpers
         {
+
+            private static CultureInfo cultureInfo = CultureInfo.InvariantCulture;
             /// <summary>
             /// Combine several hashcodes into a single new one. This implementation was grabbed from http://stackoverflow.com/a/34229665 where it is introduced 
             /// as MS implementation of GetHashCode() for strings.
@@ -202,7 +205,7 @@ public static Cache.TypeMap CreateTypeMap(Type type)
                         {
                             identifiers.Add(memberName);
                         }
-                        else if (conventionIdentifiers.Exists(x => x.ToLower() == memberName.ToLower()))
+                        else if (conventionIdentifiers.Exists(x => x.ToLower(cultureInfo) == memberName.ToLower(cultureInfo)))
                         {
                             identifiers.Add(memberName);
                         }
@@ -217,7 +220,7 @@ public static Cache.TypeMap CreateTypeMap(Type type)
                             {
                                 identifiers.Add(memberName);
                             }
-                            else if (conventionIdentifiers.Exists(x => x.ToLower() == memberName.ToLower()))
+                            else if (conventionIdentifiers.Exists(x => x.ToLower(cultureInfo) == memberName.ToLower(cultureInfo)))
                             {
                                 identifiers.Add(memberName);
                             }
@@ -486,7 +489,7 @@ internal static object Map(IDictionary<string, object> dictionary, object instan
 
                 foreach (var fieldOrProperty in fieldsAndProperties)
                 {
-                    var memberName = fieldOrProperty.Key.ToLower();
+                    var memberName = fieldOrProperty.Key.ToLower(cultureInfo);
 
                     var member = fieldOrProperty.Value;
 
@@ -505,7 +508,7 @@ internal static object Map(IDictionary<string, object> dictionary, object instan
                         if (memberType.IsClass || memberType.IsInterface)
                         {
                             // Try to find any keys that start with the current member name
-                            var nestedDictionary = dictionary.Where(x => x.Key.ToLower().StartsWith(memberName + "_")).ToList();
+                            var nestedDictionary = dictionary.Where(x => x.Key.ToLower(cultureInfo).StartsWith(memberName + "_")).ToList();
 
                             // If there weren't any keys
                             if (!nestedDictionary.Any())
@@ -524,7 +527,7 @@ internal static object Map(IDictionary<string, object> dictionary, object instan
                                 continue;
                             }
                             var regex = new Regex(Regex.Escape(memberName + "_"));
-                            var newDictionary = nestedDictionary.ToDictionary(pair => regex.Replace(pair.Key.ToLower(), string.Empty, 1),
+                            var newDictionary = nestedDictionary.ToDictionary(pair => regex.Replace(pair.Key.ToLower(cultureInfo), string.Empty, 1),
                                 pair => pair.Value, StringComparer.OrdinalIgnoreCase);
 
                             // Try to get the value of the complex member. If the member