Sega Games Co., Ltd. (Japanese: 株式会社セガゲームス Hepburn: Kabushiki gaisha Sega gēmusu), originally short for Service Games and officially styled as SEGA, is a Japanese multinational video game developer and publisher headquartered in Tokyo, Japan, with multiple offices around the world. Sega developed and manufactured numerous home video game consoles from 1983 to 2001, but the financial losses incurred from its Dreamcast console caused the company to restructure in 2001, and subsequently focus on providing software as a third-party developer. Nonetheless, Sega remains the world's most prolific arcade producer, with over 500 games in over 70 franchises on more than 20 different arcade system boards since 1981.

Sega, along with their sub-studios, are known for their multi-million selling game franchises, such as Sonic the Hedgehog, Virtua Fighter, Phantasy Star, Yakuza, and Total War. Sega's head offices are located in Tokyo. Sega's North American division, Sega of America, is headquartered in Irvine, California, having moved there from San Francisco in 2015. Sega's European division, Sega Europe, is headquartered in London.