vss2svn is a Perl script which converts Microsoft Visual SourceSafe (VSS) repositories to Subversion.

There are two versions. The version of vss2svn at tigris.org will migrate all revision history, including comments and author names. It works by checking out each revision in SourceSafe, calculating which commits are part of an atomic commit and then checking them into a Subversion database.

The version of vss2svn at pumacode is in development at the time of writing (April 2006) and claims it will do a much better conversion by reading the VSS database directly, thus giving it access to more information.