diff --git a/CSharp/Plugins/UniversalEditor.Plugins.FileSystem/DataFormats/FileSystem/StellaGames/LzmaPack/PACKDataFormat.cs b/CSharp/Plugins/UniversalEditor.Plugins.FileSystem/DataFormats/FileSystem/StellaGames/LzmaPack/PACKDataFormat.cs
new file mode 100644
index 00000000..8278490f
--- /dev/null
+++ b/CSharp/Plugins/UniversalEditor.Plugins.FileSystem/DataFormats/FileSystem/StellaGames/LzmaPack/PACKDataFormat.cs
@@ -0,0 +1,107 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using UniversalEditor.IO;
+using UniversalEditor.ObjectModels.FileSystem;
+
+namespace UniversalEditor.DataFormats.FileSystem.StellaGames.LzmaPack
+{
+	public class PACKDataFormat : DataFormat
+	{
+		private static DataFormatReference _dfr = null;
+		public override DataFormatReference MakeReference()
+		{
+			if (_dfr == null)
+			{
+				_dfr = base.MakeReference();
+				_dfr.Capabilities.Add(typeof(FileSystemObjectModel), DataFormatCapabilities.All);
+				_dfr.Filters.Add("Stella Games LzmaPack", new string[] { "*.pack" });
+			}
+			return _dfr;
+		}
+
+		protected override void LoadInternal(ref ObjectModel objectModel)
+		{
+			FileSystemObjectModel fsom = (objectModel as FileSystemObjectModel);
+			if (fsom == null) throw new ObjectModelNotSupportedException();
+
+			Reader reader = base.Accessor.Reader;
+			byte lzmaDecoderPropertiesSize = reader.ReadByte();
+			byte[] lzmaDecoderProperties = reader.ReadBytes(lzmaDecoderPropertiesSize);
+			uint fileCount = reader.ReadUInt32();
+			for (uint i = 0; i < fileCount; i++)
+			{
+				string fileName = reader.ReadLengthPrefixedString();
+				long decompressedSize = reader.ReadInt64();
+				long compressedSize = reader.ReadInt64();
+				long offset = reader.ReadInt64();
+				PACKFileAttributes fileAttributes = (PACKFileAttributes)reader.ReadUInt16();
+
+				File file = fsom.AddFile(fileName);
+				file.Size = decompressedSize;
+				file.Properties.Add("reader", reader);
+				file.Properties.Add("offset", offset);
+				file.Properties.Add("CompressedSize", compressedSize);
+				file.Properties.Add("DecompressedSize", decompressedSize);
+				file.DataRequest += file_DataRequest;
+			}
+		}
+
+		private void file_DataRequest(object sender, DataRequestEventArgs e)
+		{
+			File file = (sender as File);
+			Reader reader = (Reader)file.Properties["reader"];
+			long offset = (long)file.Properties["offset"];
+			long CompressedSize = (long)file.Properties["CompressedSize"];
+			long DecompressedSize = (long)file.Properties["DecompressedSize"];
+
+			reader.Seek(offset, SeekOrigin.Begin);
+			byte[] compressedData = reader.ReadBytes(CompressedSize);
+			byte[] decompressedData = compressedData;
+			e.Data = decompressedData;
+		}
+
+		protected override void SaveInternal(ObjectModel objectModel)
+		{
+			FileSystemObjectModel fsom = (objectModel as FileSystemObjectModel);
+			if (fsom == null) throw new ObjectModelNotSupportedException();
+
+			Writer writer = base.Accessor.Writer;
+			File[] files = fsom.GetAllFiles();
+
+			byte lzmaDecoderPropertiesSize = 0;
+			byte[] lzmaDecoderProperties = new byte[lzmaDecoderPropertiesSize];
+			writer.WriteByte(lzmaDecoderPropertiesSize);
+			writer.WriteBytes(lzmaDecoderProperties);
+
+			long offset = 1 + lzmaDecoderPropertiesSize + 4;
+			foreach (File file in files)
+			{
+				System.IO.MemoryStream ms = new System.IO.MemoryStream();
+				System.IO.BinaryWriter bw = new System.IO.BinaryWriter(ms);
+				bw.Write(file.Name);
+				bw.Close();
+				offset += ms.ToArray().Length;
+				offset += 26;
+			}
+
+			writer.WriteUInt32((uint)files.Length);
+			foreach (File file in files)
+			{
+				writer.WriteLengthPrefixedString(file.Name);
+				byte[] decompressedData = file.GetDataAsByteArray();
+				byte[] compressedData = decompressedData;
+
+				writer.WriteInt64((long)decompressedData.Length);
+				writer.WriteInt64((long)compressedData.Length);
+				writer.WriteInt64(offset);
+
+				PACKFileAttributes fileAttributes = PACKFileAttributes.None;
+				writer.WriteUInt16((ushort)fileAttributes);
+
+				offset += compressedData.Length;
+			}
+		}
+	}
+}
diff --git a/CSharp/Plugins/UniversalEditor.Plugins.FileSystem/DataFormats/FileSystem/StellaGames/LzmaPack/PACKFileAttributes.cs b/CSharp/Plugins/UniversalEditor.Plugins.FileSystem/DataFormats/FileSystem/StellaGames/LzmaPack/PACKFileAttributes.cs
new file mode 100644
index 00000000..3ee1c707
--- /dev/null
+++ b/CSharp/Plugins/UniversalEditor.Plugins.FileSystem/DataFormats/FileSystem/StellaGames/LzmaPack/PACKFileAttributes.cs
@@ -0,0 +1,14 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+
+namespace UniversalEditor.DataFormats.FileSystem.StellaGames.LzmaPack
+{
+	[Flags()]
+	public enum PACKFileAttributes : ushort
+	{
+		None = 0,
+		Compressed = 1
+	}
+}
diff --git a/CSharp/Plugins/UniversalEditor.Plugins.FileSystem/UniversalEditor.Plugins.FileSystem.csproj b/CSharp/Plugins/UniversalEditor.Plugins.FileSystem/UniversalEditor.Plugins.FileSystem.csproj
index 1034d762..78094416 100644
--- a/CSharp/Plugins/UniversalEditor.Plugins.FileSystem/UniversalEditor.Plugins.FileSystem.csproj
+++ b/CSharp/Plugins/UniversalEditor.Plugins.FileSystem/UniversalEditor.Plugins.FileSystem.csproj
@@ -138,6 +138,8 @@
     <Compile Include="DataFormats\FileSystem\SevenZip\SevenZipUnpackInfo.cs" />
     <Compile Include="DataFormats\FileSystem\SilentHill\ARC\SilentHillARCDataFormat.cs" />
     <Compile Include="DataFormats\FileSystem\SPIS\SPISDataFormat.cs" />
+    <Compile Include="DataFormats\FileSystem\StellaGames\LzmaPack\PACKDataFormat.cs" />
+    <Compile Include="DataFormats\FileSystem\StellaGames\LzmaPack\PACKFileAttributes.cs" />
     <Compile Include="DataFormats\FileSystem\StuffIt\StuffItDataFormat.cs" />
     <Compile Include="DataFormats\FileSystem\TapeArchive\TapeArchiveDataFormat.cs" />
     <Compile Include="DataFormats\FileSystem\TapeArchive\TapeArchiveRecordType.cs" />