Civilization is coming to Take-Two Interactive ( TTWO), as the video-game maker announced Monday that it has acquired the developer of the popular award-winning strategy game series. As part of the transaction, the formerly privately held Firaxis Games will become a part of Take-Two's 2K Games publishing label. The companies did not disclose the transaction's financial details. Sid Meier, the heralded developer of Civilization, Pirates and other games, will remain with Firaxis following the acquisition, said Kelley Gilmore, a spokeswoman for Firaxis. Firaxis stay in Hunt Valley, Md., after the transaction and none of its 65 employees is expected to be laid off as a result, Gilmore said. A representative of Take-Two, which is the publisher and developer of the hit Grand Theft Auto franchise, did not return a call seeking comment. Take-Two reached an agreement to publish Firaxis' games in January. The companies released Civilization IV last month. By bringing Firaxis' titles in-house, Take-Two should see larger gross margins from the sales of those games. However, the company will now be responsible for Firaxis' overhead. The move represents the latest effort by Take-Two to diversify beyond Grand Theft Auto. As part of that effort, the company launched its 2K Games and 2K Sports publishing labels earlier this year to showcase games that were not developed by its Rockstar studios, the division behind Grand Theft Auto. Take-Two's diversification effort has seen mixed success. Sales of the company's basketball title -- one of the first games of this year's sports lineup -- have been disappointing. And despite the effort, Grand Theft Auto still represents a disproportionate amount of the company's sales and earnings. The acquisition is also the latest in a series of moves by larger publishers to snap up smaller development shops. Electronic Arts ( ERTS) and Midway Games ( MWY) also have bought developers in the last 18 months. Shares of Take-Two closed regular trading down a penny to $18.20. The stock was unchanged after hours.