static void Main() { string assemblyName1 = @"System.Windows.Forms, Version=2.0.0.0, Culture=neutral,PublicKeyToken=b77a5c561934e089"; string assemblyName2 = @"System.Windows.Forms, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089"; // this may be of interest as well // I think you can use usedAssemblies[ i ] //var usedAssemblies = AppDomain.CurrentDomain.GetAssemblies(); var assembly1 = Assembly.Load(assemblyName1); var assembly2 = Assembly.Load(assemblyName2); Console.ReadLine(); }