CSPromod (CSP, for short) is a 100% custom-coded Source engine modification. Its goal is to bring the gameplay, feel, and competitive spirit of the original Counter-Strike to the Source engine, along with improved graphics and new features.
What do I need to play CSPromod?
A legitimate, Steam-based copy of Counter-Strike: Source or a (free) copy of Team Fortress 2 both by Valve Software and run it at least once. You will also need to download "Source SDK Base 2007" from the "Tools" tab in Steam.