2K Games has signed a deal to release four PC strategy games via Valve's digital distribution service, Steam.
As a result, Steam users will be able to download Civilization III and IV, along with Shattered Union and Sid Meier's Pirates!. The games will be available later this week.
Valve president Gabe Newell welcomed the deal, commenting, "We look forward to delivering more from 2K in the future."
2K's Paul Crockett added: "We are excited to add Valve to our roster of partners in the digital distribution area. Being included in their vast network will assist us in expanding the reach of our products to a much larger audience."