diff --git a/MBS.Framework/Diagnostics/Logger.cs b/MBS.Framework/Diagnostics/Logger.cs
new file mode 100644
index 0000000..0ab7f38
--- /dev/null
+++ b/MBS.Framework/Diagnostics/Logger.cs
@@ -0,0 +1,110 @@
+//
+//  Logger.cs
+//
+//  Author:
+//       beckermj <>
+//
+//  Copyright (c) 2023 ${CopyrightHolder}
+//
+//  This program is free software: you can redistribute it and/or modify
+//  it under the terms of the GNU General Public License as published by
+//  the Free Software Foundation, either version 3 of the License, or
+//  (at your option) any later version.
+//
+//  This program is distributed in the hope that it will be useful,
+//  but WITHOUT ANY WARRANTY; without even the implied warranty of
+//  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+//  GNU General Public License for more details.
+//
+//  You should have received a copy of the GNU General Public License
+//  along with this program.  If not, see <http://www.gnu.org/licenses/>.
+using System;
+using System.Collections.Generic;
+
+namespace MBS.Framework.Diagnostics
+{
+	public class Logger
+	{
+		public void Write(string value)
+		{
+			Console.Error.Write(value);
+		}
+		public void WriteLine(string value)
+		{
+			Console.Error.WriteLine(value);
+		}
+
+		public string ProjectName { get; set; }
+
+		private class FuncInfo
+		{
+			public string FileName;
+			public string FunctionName;
+
+			public FuncInfo(string filename, string functionName)
+			{
+				FileName = filename;
+				FunctionName = functionName;
+			}
+		}
+
+		private Stack<FuncInfo> _funcInfo = new Stack<FuncInfo>();
+		public void EnterFunction(string filename, string funcName)
+		{
+			Console.Error.WriteLine("entering function {0}:{1}", filename, funcName);
+			_funcInfo.Push(new FuncInfo(filename, funcName));
+		}
+		public void LeaveFunction()
+		{
+			FuncInfo f = _funcInfo.Pop();
+			Console.Error.WriteLine("leaving function {0}:{1}", f.FileName, f.FunctionName);
+		}
+
+		private FuncInfo CurrentFunction
+		{
+			get
+			{
+				if (_funcInfo.Count > 0)
+				{
+					return _funcInfo.Peek();
+				}
+				return null;
+			}
+		}
+
+		private void WriteMessage(string filename, int lineNumber, MessageSeverity severity, string funcName, string message)
+		{
+			WriteMessage(filename, lineNumber, ProjectName, severity, funcName, message);
+		}
+		private void WriteMessage(string filename, int lineNumber, string projName, MessageSeverity severity, string funcName, string message)
+		{
+			string severityStr = null;
+			switch (severity)
+			{
+				case MessageSeverity.Error: severityStr = "CRITICAL"; break;
+				case MessageSeverity.Message: severityStr = "MESSAGE"; break;
+				case MessageSeverity.Warning: severityStr = "WARNING"; break;
+				case MessageSeverity.None: severityStr = null; break;
+			}
+			if (severityStr == null)
+			{
+				WriteLine(String.Format("({0}:{1}): {2}: {3}: {4}: {5}", filename, lineNumber, projName, DateTime.Now.ToString(), funcName, message));
+			}
+			else
+			{
+				WriteLine(String.Format("({0}:{1}): {2}[{3}]: {4}: {5}: {6}", filename, lineNumber, projName, severityStr, DateTime.Now.ToLongTimeString(), funcName, message));
+			}
+		}
+		public void WriteAssertFailed(string filename, int lineNumber, string projName, MessageSeverity severity, string funcName, string call, string parms)
+		{
+			WriteMessage(filename, lineNumber, projName, severity, funcName, String.Format("assertion '{0} ({1})' failed", call, parms));
+		}
+
+		public void WriteMismatch(int lineNumber, MessageSeverity severity, string message, object expectedValue, object actualValue)
+		{
+			string filename = CurrentFunction?.FileName;
+			string funcName = CurrentFunction?.FunctionName;
+			WriteMessage(filename, lineNumber, severity, funcName, String.Format("{0}: expected {1}, got {2}", message, expectedValue, actualValue));
+		}
+	}
+}
diff --git a/MBS.Framework/MBS.Framework.csproj b/MBS.Framework/MBS.Framework.csproj
index 1f17423..f2c5084 100644
--- a/MBS.Framework/MBS.Framework.csproj
+++ b/MBS.Framework/MBS.Framework.csproj
@@ -141,6 +141,7 @@
     <Compile Include="ProgressEvent.cs" />
     <Compile Include="ICustomPlugin.cs" />
     <Compile Include="StringBuilderExtensions.cs" />
+    <Compile Include="Diagnostics\Logger.cs" />
     <Compile Include="PropertyBag.cs" />
     <Compile Include="PropertyValueChangedEvent.cs" />
     <Compile Include="PropertyValueChangingEvent.cs" />
@@ -156,6 +157,7 @@
     <Folder Include="Scripting\Strings\" />
     <Folder Include="Settings\" />
     <Folder Include="UserInterface\" />
+    <Folder Include="Diagnostics\" />
   </ItemGroup>
   <ItemGroup>
     <None Include="MemorySettingsProvider.cs" />