diff --git a/SabreTools.DatFiles.Test/DatFileTests.cs b/SabreTools.DatFiles.Test/DatFileTests.cs
new file mode 100644
index 00000000..08e87470
--- /dev/null
+++ b/SabreTools.DatFiles.Test/DatFileTests.cs
@@ -0,0 +1,149 @@
+namespace SabreTools.DatFiles.Test
+{
+    public class DatFileTests
+    {
+        #region Constructor
+
+        // TODO: Write Constructor tests
+
+        #endregion
+
+        #region FillHeaderFromPath
+
+        // TODO: Write FillHeaderFromPath tests
+
+        #endregion
+
+        #region ResetDictionary
+
+        // TODO: Write ResetDictionary tests
+
+        #endregion
+
+        #region SetHeader
+
+        // TODO: Write SetHeader tests
+
+        #endregion
+
+        #region ExecuteFilters
+
+        // TODO: Write ExecuteFilters tests
+
+        #endregion
+
+        #region ParseFile
+
+        // TODO: Write ParseFile tests
+
+        #endregion
+
+        #region ParseAddHelper
+
+        // TODO: Write ParseAddHelper tests
+
+        #endregion
+
+        #region ParseAddHelperDB
+
+        // TODO: Write ParseAddHelperDB tests
+
+        #endregion
+
+        #region WriteToFile
+
+        // TODO: Write WriteToFile tests
+
+        #endregion
+
+        #region WriteToFileDB
+
+        // TODO: Write WriteToFileDB tests
+
+        #endregion
+
+        #region CreatePrefixPostfix
+
+        // TODO: Write CreatePrefixPostfix tests
+
+        #endregion
+
+        #region CreatePrefixPostfixDB
+
+        // TODO: Write CreatePrefixPostfixDB tests
+
+        #endregion
+
+        #region ProcessItemName
+
+        // TODO: Write ProcessItemName tests
+
+        #endregion
+
+        #region ProcessItemNameDB
+
+        // TODO: Write ProcessItemNameDB tests
+
+        #endregion
+
+        #region ProcessNullifiedItem
+
+        // TODO: Write ProcessNullifiedItem tests
+
+        #endregion
+
+        #region ProcessNullifiedItemDB
+
+        // TODO: Write ProcessNullifiedItemDB tests
+
+        #endregion
+
+        #region GetSupportedTypes
+
+        // TODO: Write GetSupportedTypes tests
+
+        #endregion
+
+        #region GetMissingRequiredFields
+
+        // TODO: Write GetMissingRequiredFields tests
+
+        #endregion
+
+        #region ContainsWritable
+
+        // TODO: Write ContainsWritable tests
+
+        #endregion
+
+        #region ContainsWritableDB
+
+        // TODO: Write ContainsWritableDB tests
+
+        #endregion
+
+        #region ResolveNames
+
+        // TODO: Write ResolveNames tests
+
+        #endregion
+
+        #region ResolveNamesDB
+
+        // TODO: Write ResolveNamesDB tests
+
+        #endregion
+
+        #region ShouldIgnore
+
+        // TODO: Write ShouldIgnore tests
+
+        #endregion
+
+        #region GetDuplicateSuffix
+
+        // TODO: Write GetDuplicateSuffix tests
+
+        #endregion
+    }
+}
\ No newline at end of file
diff --git a/SabreTools.DatFiles.Test/SabreTools.DatFiles.Test.csproj b/SabreTools.DatFiles.Test/SabreTools.DatFiles.Test.csproj
new file mode 100644
index 00000000..4c0bb43d
--- /dev/null
+++ b/SabreTools.DatFiles.Test/SabreTools.DatFiles.Test.csproj
@@ -0,0 +1,30 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+    <PropertyGroup>
+        <TargetFrameworks>net6.0;net8.0;net9.0</TargetFrameworks>
+        <IsPackable>false</IsPackable>
+        <LangVersion>latest</LangVersion>
+        <Nullable>enable</Nullable>
+    </PropertyGroup>
+
+    <ItemGroup>
+        <ProjectReference Include="..\SabreTools.Core\SabreTools.Core.csproj" />
+        <ProjectReference Include="..\SabreTools.DatFiles\SabreTools.DatFiles.csproj" />
+        <ProjectReference Include="..\SabreTools.DatItems\SabreTools.DatItems.csproj" />
+        <ProjectReference Include="..\SabreTools.FileTypes\SabreTools.FileTypes.csproj" />
+    </ItemGroup>
+
+    <ItemGroup>
+        <PackageReference Include="coverlet.collector" Version="6.0.3">
+            <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
+            <PrivateAssets>all</PrivateAssets>
+        </PackageReference>
+        <PackageReference Include="Microsoft.NET.Test.Sdk" Version="17.12.0" />
+        <PackageReference Include="xunit" Version="2.9.2" />
+        <PackageReference Include="xunit.runner.visualstudio" Version="3.0.0">
+            <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
+            <PrivateAssets>all</PrivateAssets>
+        </PackageReference>
+    </ItemGroup>
+
+</Project>
\ No newline at end of file
diff --git a/SabreTools.DatFiles/DatFile.cs b/SabreTools.DatFiles/DatFile.cs
index c12d335b..b2beac1c 100644
--- a/SabreTools.DatFiles/DatFile.cs
+++ b/SabreTools.DatFiles/DatFile.cs
@@ -61,7 +61,7 @@ namespace SabreTools.DatFiles
             _logger = new Logger(this);
             if (datFile != null)
             {
-                Header = datFile.Header;
+                Header = (DatHeader)datFile.Header.Clone();
                 Items = datFile.Items;
                 ItemsDB = datFile.ItemsDB;
             }
@@ -124,7 +124,7 @@ namespace SabreTools.DatFiles
         /// <param name="datHeader">Replacement header to be used</param>
         public void SetHeader(DatHeader datHeader)
         {
-            Header = (DatHeader)datHeader.Clone();;
+            Header = (DatHeader)datHeader.Clone();
         }
 
         #endregion
@@ -680,6 +680,7 @@ namespace SabreTools.DatFiles
         /// Get supported types for write
         /// </summary>
         /// <returns>List of supported types for writing</returns>
+        /// TODO: Make this into a property instead of a method
         protected virtual ItemType[] GetSupportedTypes()
         {
             return Enum.GetValues(typeof(ItemType)) as ItemType[] ?? [];
diff --git a/SabreTools.sln b/SabreTools.sln
index 2770c7b7..fd352795 100644
--- a/SabreTools.sln
+++ b/SabreTools.sln
@@ -34,6 +34,8 @@ Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "SabreTools.FileTypes.Test",
 EndProject
 Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "SabreTools.DatItems.Test", "SabreTools.DatItems.Test\SabreTools.DatItems.Test.csproj", "{5BB75FB7-D9D0-493D-AF31-A371882A44A4}"
 EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "SabreTools.DatFiles.Test", "SabreTools.DatFiles.Test\SabreTools.DatFiles.Test.csproj", "{5492C6EA-02CD-4862-80A8-A4971EAEE8E3}"
+EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Any CPU = Debug|Any CPU
@@ -138,6 +140,14 @@ Global
 		{5BB75FB7-D9D0-493D-AF31-A371882A44A4}.Release|Any CPU.Build.0 = Release|Any CPU
 		{5BB75FB7-D9D0-493D-AF31-A371882A44A4}.Release|x64.ActiveCfg = Release|Any CPU
 		{5BB75FB7-D9D0-493D-AF31-A371882A44A4}.Release|x64.Build.0 = Release|Any CPU
+		{5492C6EA-02CD-4862-80A8-A4971EAEE8E3}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{5492C6EA-02CD-4862-80A8-A4971EAEE8E3}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{5492C6EA-02CD-4862-80A8-A4971EAEE8E3}.Debug|x64.ActiveCfg = Debug|Any CPU
+		{5492C6EA-02CD-4862-80A8-A4971EAEE8E3}.Debug|x64.Build.0 = Debug|Any CPU
+		{5492C6EA-02CD-4862-80A8-A4971EAEE8E3}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{5492C6EA-02CD-4862-80A8-A4971EAEE8E3}.Release|Any CPU.Build.0 = Release|Any CPU
+		{5492C6EA-02CD-4862-80A8-A4971EAEE8E3}.Release|x64.ActiveCfg = Release|Any CPU
+		{5492C6EA-02CD-4862-80A8-A4971EAEE8E3}.Release|x64.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE