The .NET Framework has been RTM'ed in November 2006 (almost 1 year!), but there still seems to be a lot of confusion about the Framework. A lot of people still don't realise that the .NET Framework still uses the 2.0 version of the Common Language Runtime (CLR). Since this additive release to the .NET Framework, the CLR version number is no longer coupled to the .NET Framework version number. As a result, the 3.0 Framework is completely backward compatible with the earlier version and your 2.0 based applications will continue to run without modifications.