Google is to provide office space and assistance to new technology companies in London's "Silicon Roundabout".
The company has leased a seven-storey building in the Old Street area, where many start-up firms are based.
Prime Minister David Cameron has signalled his desire to turn the area into "one of the world's great technology centres".
About 300 companies are now working in the area, according to Tech City, the body set up to promote the initiative.
Google said that the building, in Bonhill Street, would host "a range of activities, such as speaker series, hackathons, training workshops and product demonstrations" in addition to providing workspace for new companies.