Black Mesa is a complete re-creation of the game Half-Life, utilizing the Source engine. Black Mesa will let you re-visit the world that started the Half-Life continuum. Learn more here.
We have always gone for a "when it's done" approach. We have however committed to releasing in the year 2009.

The only requirement to play Black Mesa will be that you own any Source Engine game on Steam. For a detailed list see here.
Black Mesa is a free modification; The developers will never charge you for playing mainly because we wouldn't want to make people pay to play, but also because it would be illegal to do so. As long as you have a copy of any source engine game on steam, Black Mesa will cost you nothing.
