Sega is a very big and old company. It has a lot of divisions, and some, such as AM2, are known in their own right. This page is an attempt to sort out what part of Sega did what.

Sega Enterprises Ltd.

Currently Sega Corporation. Everyone's favorite video game maker. Owned from 1984-2004 by the CSK Group, and from then on by Sammy Entertainment.

Here's the history of the studios as we can tell so far:

Opened their first development division sometime around 1982. Two more development divisions were opened in the following years, possibly around 1984. After the Mega Drive was released, Sega seems to have split their amusement and consumer staff into separate divisions, creating the famous AM divisions. By 1991 there seem to have been three amusement and three consumer divisions. Sometime in the mid-to-late '90s, all the consumer divisions were renamed to be AM divisions, and the amusement/consumer distinction was dropped. In 2000, all of the existing studios became separate entities and given their own names. In 2004, around when the Sammy acquisition took place, most of the studios were folded back in, losing their names and given more generic ones.

Sega of America did not run any development until the Sega Technical Institute was opened in 1991. Several other studios were run by SoA throughout the '90s with varying degrees of success, with most closing down after only a few years in operation.

Development Studios

AM1

Renamed into WOW Entertainment in the 2000 restructuring. In the 2004 Sammy merger, AM1 merged with AM7 to form Sega WOW, which was soon after renamed Amusement Software R&D1.

As AM1

• to be completed...

As WOW Entertainment

• Alien Front Online (AC/DC)
• Candy Stripe: Minarai Tenshi (DC)
• Gekitou Pro Yakyuu: Mizushima Shinji All-Stars VS Pro Yakyuu (PS2/GCN)
• Get Bass 2 / Sega Bass Fishing (AC/DC)
• Home Run King (GCN)
• The House of the Dead III (AC/XBX)
• The Pinball of the Dead (GBA)
• Sega GT (AC)
• Sega GT 2002 (XBX)
• Sega GT Online (XBX)
• Sports Jam (AC/DC)
• Vampire Night (AC)
• World Series Baseball 2K1 (DC)

AM2

Yu Suzuki's team. Responsible for Out Run, etc. Merged with CRI at one point during Sega's nineties restructuring.

• Virtua Fighter series, Virtua Cop series, Daytona USA, Out Run series, Shenmue series, Space Harrier, After Burner, Ferrari F355 Challenge, Fighting Vipers...

AM3

Now known as Hitmaker.

• Crazy Taxi, Virtual On, Virtua Tennis series...
• Games developed by AM3/Hitmaker according to PtWiki

AM4

Also sometimes called AM11. Seems to have been a new division opened around 1998 by a handful of former AM2 staffers, including Daytona USA game designer Toshihiro Nagoshi. Became known as Amusement Vision in 2000. In 2004, some of the staff from Smilebit were brought to this division and it became New Entertainment R&D1.

As AM4/AM11

• Daytona USA 2: Battle on the Edge (AC)
• SpikeOut (AC)

As Amusement Vision

• Daytona USA / Daytona USA 2001 (DC)
• F-Zero AX (AC)
• F-Zero GX (GCN) (Nintendo)
• Monkey Ball (AC)
• Spikers Battle (AC)
• Super Monkey Ball (GCN)
• Super Monkey Ball 2 (GCN)
• Super Monkey Ball Jr. (GBA/NGA)
• Ollie King (AC)
• Planet Harriers (AC)
• Virtua NBA (AC)
• Virtua Striker 2002 / Virtua Striker 3 Ver. 2002 (GCN)
• Virtua Striker 2 (AC)
• Virtua Striker 3 Ver. 2002 (AC)

As New Entertainment R&D1

• Spikeout: Battle Street (XBX)

co-developed with DIMPS

• Super Monkey Ball Deluxe (PS2/XBX)
• Super Monkey Ball: Banana Blitz / Super Monkey Ball: Uki Uki Party Daishuugou (WII)
• Super Monkey Ball: Touch & Roll (NDS)
• Yakuza / Ryu ga Gotoku (PS2)
• Yakuza 2 / Ryu Ga Gotoku 2 (PS2)

Notes:

• Sukeban deka (Master System): Produced by 4th R&D

Is 4th R&D the same thing as AM4?

AM5

Split off from the Sega Rally Championship team at AM3, creating an AM annex division sometimes called AM12. Became known as Sega Rosso in 2000. Merged back into AM3/Hitmaker in 2004 as Amusement Software R&D3.

As AM5

• Card Captor Sakura: Tomoyo no Video Daisakusen (DC)
• Sega Touring Car Championship (AC)
• Star Wars Trilogy Arcade (AC)

As Sega Rosso

• Cosmic Smash (AC/DC)
• EA Sports NASCAR Arcade (AC)
• Initial D: Arcade Stage (AC)
• Initial D: Arcade Stage 2 (AC)
• Initial D: Special Stage (PS2)
• Initial D: Version 3 (AC)
• La Keyboard (AC)
• Soul Surfer (AC)
• Star Wars Racer Arcade (AC)

AM6

Initially Consumer Software Division #1 and PC Software Division, eventually merged into AM6, later known as Smilebit. The bulk of the staff now make up Amusement Software Sports & Design, though some were moved to New Entertainment R&D1.

When the Saturn was in development, several teams were formed at CS1: Team Andromeda, Team Aquila, Team Vega, and G9 Team. These teams were folded back in around 1998.

As AM6/CS1

• to be completed...

Team Andromeda

• Panzer Dragoon (SAT)
• Panzer Dragoon II Zwei (SAT)
• Panzer Dragoon Saga / Azel: Panzer Dragoon RPG (SAT)

Team Aquila

• Sega Worldwide Soccer '97 / Victory Goal Worldwide Edition (SAT)
• Victory Goal (SAT)
• Victory Goal '96 (SAT)
• Worldwide Soccer: Sega International Victory Goal Edition / Sega International Victory Goal (SAT)

Team Vega

• J.League Pro Soccer Club o Tsukurou! (SAT)

G9 Team

• Pro Yakyuu Greatest Nine '97 (SAT)

As Smilebit

• 90 Minutes: Sega Championship Football (DC)
• Baseball Advance / Greatest Nine (GBA)
• De La Jet Set Radio (DC)
• Gunvalkyrie (XBX)
• Hundred Swords (DC)
• Jet Set Radio / Jet Grind Radio (DC)
• JSRF: Jet Set Radio Future (XBX)
• Motto Pro Yakyuu Team o Tsukurou! (DC)
• Ollie King (AC)
• Panzer Dragoon Orta (XBX)
• Pro Yakyuu Team o Tsukurou! 2 (PS2)
• Soccer Tsuku 2002: J.League Pro Soccer Club o Tsukurou! (PS2)
• Soccer Tsuku Tokudaigou: J.League Pro Soccer Club o Tsukurou! (DC)
• Soccer Tsuku Tokudaigou 2: J.League Pro Soccer Club o Tsukurou! (DC)
• The Typing of the Dead (DC/AC)

AM7

Known as Overworks after 2000, merged in 2004 with AM1 to form Sega Wow.

• Streets of Rage (???), Shinobi series, Skies of Arcadia, Phantasy Star series...
• Games developed by AM7/Overworks, according to PtWiki

AM8

Commonly known as Sonic Team. Originally created around 1990 as Consumer Division #3. Now known officially as Global Entertainment Software Dept. #1. Headed up by Yuji Naka until his departure from Sega in 2006.

Unlike most of the other divisions at Sega, Sonic Team has been known under this name since their inception. The Sonic Team name is now used for games developed or produced by Sega's Global Entertainment Software divisions.

As Sonic Team

• Billy Hatcher and the Giant Egg / Giant Egg: Billy Hatcher no Daibouken (GCN)
• Burning Rangers (SAT)
• Christmas NiGHTS (SAT)
• Chu Chu Rocket! (DC/GBA)
• NiGHTS: into Dreams... (SAT)
• Phantasy Star Online (DC)
• Phantasy Star Online Ver. 2 (DC)
• Phantasy Star Online: Episode I & II (GCN/XBX)
• Phantasy Star Online: Episode III: C.A.R.D. Revolution (GCN)
• Puyo Pop / Puyo Puyo Fever (GCN/XBX/DC/AC)
• Samba de Amigo (AC/DC)
• Sonic Adventure (DC)
• Sonic Adventure DX: Director's Cut (GCN)
• Sonic Battle (GBA)
• Sonic Jam (SAT)
• Sonic Pinball Party (GBA)

co-developed with Jupiter

• Sonic The Hedgehog (MD)
• Sonic The Hedgehog 2 (MD)

co-developed with Sega Technical Institute

• Sonic The Hedgehog 3 (MD)
• Sonic & Knuckles (MD)

As Global Entertainment Software Dept. #1

• Phantasy Star Universe (PS2/XBX)
• Sega Superstars (PS2)
• Sonic and the Secret Rings / Sonic to Himitsu no Ring (WII)
• Sonic The Hedgehog (PS3/X360)

Sonic Team USA

Opened by Sonic Team in San Francisco in 1999, changed names to Sega Studios USA in 2004.

As Sonic Team USA

• Sonic Adventure 2 (DC)
• Sonic Adventure 2: Battle (GCN)
• Sonic Heroes (PS2/GCN/XBX)

As Sega Studios USA

• NiGHTS: Journey of Dreams / NiGHTS: Hoshi Furu Yoru no Monogatari (WII)
• Shadow the Hedgehog (PS2/GCN/XBX)

AM9

Also known as United Game Artists. A small team originally created as AM Annex. Effecitvely merged with Sonic Team in 2003, now officially known as Global Entertainment Software Dept. #2. Headed by Tetsuya Mizuguchi until he left to start his own company Q Entertainment in 2003, now run by Takashi "Thomas" Yuda.

As AM9/AM Annex

• Sega Rally Championship (development assistance)
• Sega Rally 2 (development assistance)

As United Game Artists

• Rez (DC/PS2)
• Space Channel 5 (DC/PS2)
• Space Channel 5 Part 2 (DC/PS2)

As Global Entertainment Software Dept. #2

• Astro Boy (PS2)
• Feel the Magic XX/XY / Kimi no Tame Nara Shineru / Project Rub (NDS)
• Sonic Riders (PS2/GCN/XBX) (production, developed by Now Production)
• The Rub Rabbits / Akachan wa Doko Kara Kuru no? (NDS)

Wavemaster

Formerly known as Sega Digital Media, sometimes referred to as AM10. Specializes in music tools and sound design, and only did game development for a short time. Unlike the former AM divisions, Wavemaster remains as its own company even after the 2004 Sega-Sammy merger.

• New Roommania: Porori Seishun (PS2)
• Roomania #203 (DC/PS2)
• SWITCH (PS2)

Sega WOW

Result of merger between Wow Entertainment and Overworks in early 2004. Now officially known as Amusement Software R&D1.

As Sega WOW

• Nightshade / Kunoichi (PS2)

As Amusement Software R&D1

• Blood Will Tell: Tezuka Osamu's Dororo / Dororo (PS2)

CRI

CSK Research Institute. Part of the CSK Group that owned Sega from 1984 until 2004. Established in 1983, but did no game development prior to 1990. Game development staff were merged into Sega AM2 in August 2001, with the tools staff becoming CRI Middleware, which concentrates solely on multi-platform middleware.

Genesis/Mega Drive

• Dyna Brothers
• Dyna Brothers 2
• Galaxy Force II
• Ichidant-R
• Mega-Lo-Mania (Japanese localization)

Sega CD/Mega CD

• After Burner III
• Wing Commander (development assistance)

Game Gear

• Tant-R

32X

• Zaxxon's Motherbase 2000 / Parasquad

Saturn

• 2do Arukotowa Sando-R
• Cyber Troopers Virtual On
• Kidou Senshi Gundam (Bandai)
• Kidou Senshi Gundam: Ghiren no Yabou (Bandai)
• Kidou Senshi Gundam: Ghiren no Yabou Kouryaku Shireisho (Bandai)
• Kunoichi Torimonochou
• Sadamoto Yoshiyuki Illustrations (Gainax)
• Sega Touring Car Championship

Dreamcast

• Aero Dancing i
• AeroWings / Aero Dancing featuring Blue Impulse
• AeroWings 2: Air Strike / Aero Dancing F
• Cyber Troopers Virtual On: Oratorio Tangram
• Surf Rocket Racers (Crave Entertainment)
• TNN Motorsports: Hardcore Heat / Buggy Heat

G-Sat

Main article: G-Sat

Game development company started by Sega and advertising agency Asatsu-DK.

• Doraemon: Yomo Dorobou to 7-nin no Gozans (MD)
• Ishii Hisaichi no Daisekai (MCD)

Nextech

Formed in 1992 as Gau Entertainment by former Wolf Team employees. In 1997, it was bought out by Sega and became a wholly-owned subsidiary. In 1998, it merged with Sonic Team. After a management buy-out in 2003, it regained its independence. In 2005, it changed its name to Nex Entertainment.

Santos/Megasoft

Small developer acquired by Sega in 1991 and renamed Megasoft. Is this the same Santos that released Air Grave and Stahlfeder on PS1? Some of the people working here seem to have ended up at AM6 and Wavemaster.

As Santos

• Battle Golfer Yui (MD)
• JuJu Densetsu / Toki: Going Ape Spit (MD)
• Mahjong Cop Ryuu: Hakurou no Yabou (MD)

As Megasoft

• Aa Harimanada (MD)
• Dr. Robotnik's Mean Bean Machine (MD)
• The Super Shinobi II / Shinobi III: Return of the Ninja Master (MD)

Sega Technical Institute

Main developers of Sonic 2, disbanded after the cancellation of Sonic X-Treme.

• Comix Zone (MD)
• Die Hard Arcade / Dynamite Deka (AC/SAT)

Together with AM1

• Kid Chameleon / Chameleon Kid (MD)
• Sonic The Hedgehog 2 (MD)

Together with Sonic Team

• Sonic Spinball (MD) (design and production)

Programmed by Polygames

• Sonic X-Treme (unreleased) (SAT)
• The Ooze (MD)

Sonic 3 and Sonic & Knuckles were also developed at the STI facilities, but almost entirely by the Japanese staff from Sonic Team.

Interactive Designs/Sega interActive

US studio based in Los Angeles. Acquired by Sega in 1993, becoming Sega interActive, and closed down sometime around 1995.

• Disney's Bonkers (MD)
• Disney's Darkwing Duck (PCE)
• Disney's TaleSpin (MD/GG/PCE)
• Eternal Champions (MD)
• Eternal Champions: Challenge From the Dark Side (MCD)
• Garfield: Caught in the Act (MD)
• Greendog: The Beached Surfer Dude! (MD/GG)
• Home Alone 2: Lost in New York (MD)
• NBA Action Starring David Robinson (GG)
• Seven Cities of Gold: Commemorative Edition (DOS)
• Sonic Spinball (SMS/GG)
• Star Wars Arcade (32X)
• Tom Mason's Dinosaurs for Hire (MD)

Sega Midwest Studio

Main article: Sega Midwest Studio

• NHL All-Star Hockey '95 (MD)
• World Heroes (MD)

Sega Multimedia Studio

Established in 1993 to create FMV games. Closed in 1995.

• Jurassic Park (MCD)
• Wild Woody (MCD)

SegaSoft

Joint venture between Sega and CSK, founded in 1995 in America. Did PC ports of Sega games. Closed in 2000.

• Games developed by SegaSoft according to EnWiki

Production and Publishing Divisions

Sega Enterprises, Inc.

American subsidiary in the early eighties. Published and supervised the ports of Sega games to home computers and consoles. Did they have any in-house programmers? Did they make any arcade games of their own?

Shows up on arcade flyers and home releases from 1982-1984.

Sega Electronics, Inc.

Operated alongside Enterprises, Inc. Was this the American arcade division with Enterprises forming the home division?

Shows up only on arcade flyers from 1982-1983. The flyer for Champion Baseball (1983) shows the old Sega Electronics address with the Sega Enterprises name, so presumably operations were consolidated under one name.

Sega of America

Appears to have been established in 1986. The main Sega entity in North America since then. Ran a number of studios throughout the '90s.

• Sega interActive (1993-1995)
• Sega Midwest Studio (1994-1995)
• Sega Multimedia Studio (1993-1995)
• Sega Technical Institute (1991-1997)
• SegaSoft (1995-2000)
• maybe more...?

3D-AGES

Partnership between Sega and D3 Publisher formed in October 2002 to publish the Sega Ages 2500 line of PS2 remakes. This partnership ended in 2004 after 15 volumes at which point Sega continued the series on its own. Many of the remakes and ports were handled by regular D3 partners such as Tamsoft, and regular Sega partners such as SIMS.

Deep Water

Sega of America's "mature" label. Only used for two releases, MCD Eternal Champions and MD X-Perts, before being depreciated.

RED Entertainment

Founded in 1976 as Red Company. Bought by Sega in 2002, left the Sega sphere again in November 2005 in a management buy-out.

• Sakura taisen, Tengaimakyô, Gungrave, Kita e...

Yonezawa PR21

Partyroom 21 was the game development office of toy maker Yonezawa. Published a range of software for Famicom before Yonezawa was bought by Sega in 1994. After the buyout, the company changed name to Sega Yonezawa, which it was known as until it was merged into Sega Toys in 1998.

Esco Boueki

aka Esco Trading. Distribution company started in 1969 by future Sega CEO Hayao Nakayama. Purchased in 1979 by Sega.

To be continued...