Eidos Interactive has signed a deal with gaming firm Valve to deliver dozens of new and existing PC titles via the Steam digital download network.

The first agreement includes complete franchise sets of classics such as Tomb Raider, Commandos and some of the Hitman series.

Eidos will also be bringing Tomb Raider: Anniversary, Championship Manager 2007 and more to the service.

Gabe Newell, co-founder and president of Valve, said: "Offering legendary action franchises in complete sets and working with Eidos to deliver new releases is a great step forward in our efforts to expand Steam's offerings in ways that provide highest value to customers."

Tom Marx, senior business development manager of new media at Eidos, added: "Steam represents an opportunity to distribute our games electronically to millions of gamers around the world.

"It also provides a direct connection to these extremely active PC influencers who frequent Steam as a source for new content and information.

"As a result of being a spotlight feature on Steam this year, we expect to see sales of Tomb Raider: Anniversary benefit across all channels."