Sonic Team
The initial team formed in 1990 and was composed of developers from Sega's Consumer Development division, including programmer Yuji Naka, artist Naoto Ohshima, and level designer Hirokazu Yasuhara. The team took the name Sonic Team in 1991 with the release of "Sonic the Hedgehog" for the Sega Genesis. The game was a major success that contributed to millions of Genesis sales. The next "Sonic" games were developed by Naka and Yasuhara in America at Sega Technical Institute, while Ohshima worked on "Sonic CD" in Japan. Naka returned to Japan in late 1994 to become the head of CS3, later renamed R&D #8. During this time, the division took on the Sonic Team brand but developed games that do not feature Sonic, such as "Nights into Dreams" (1996) and "Burning Rangers" (1998).
Sega Technical Institute
Sega Technical Institute (STI) was an American development division of Sega. Founded by Atari veteran Mark Cerny in 1991, the studio sought to combine elite Japanese developers, including Sonic Team programmer Yuji Naka and his team, with new American talent. STI developed a number of "Sonic the Hedgehog" games, as well as other games for the Sega Genesis, before it was closed at the end of 1996.