Ken Williams (Born October 30th, 1954) co-founded Sierra On-Line, Inc. as On-Line Systems in 1979 with his wife, Roberta. Prior to founding Sierra, he worked for and headed several consulting companies and professional software firms. He served as President (1979-1981;1983-1995), Chairman (1988-1996), and CEO (1979-1996/1997.) In Sierra's first years he also acted as a programmer on many of their earliest products, acting as the sole programmer of Sierra's very first game Mystery House, the first adventure game with graphics and one the first computer games in general to have graphics.
Mystery House was released on May 5th, 1980 and truly marked the "birth" of Sierra. Ken and Roberta packaged the game and it's manual in make-shift zip-loc bags and would distribute the game to every local computer game store and retailer they could find. Much to their surprise, the game was a massive hit for the time, selling over 10,000 companies within the first few months; Their house (which was listed as the 'headquarters' in the game's documentation) began getting flooded with phone calls about the game, and thus Ken and Roberta began both to hire employees to help with the massive load and look for office space, which was eventually found in the small town of Oakhurst, which rested near the foothills of Yosemite. To reflect the new company's location, On-Line Systems became Sierra On-Line, Inc. in 1982, a name which the company kept until 2002.
Sale to CUCEdit
Sierra was sold in July 1996 to CUC International, Inc for $1.2 billion in stock. After this point, Ken's role in Sierra for approximately the next six months to a year becomes very unclear. What is known is that in September 1996 he was named a Vice Chairman and Member of the Office of the President of CUC International, Inc., making him a board member and shareholder in CUC,  and that his duties were expanded in January 1997. He was listed in the September 1996 press release announcing his appointment to the position of CUC's Vice Chairman and Member of the Office of the President as Sierra's CEO.
Ken claims to have resigned as CEO the very day the sale closed--July 24th 1996; Yet in archived postings on Usenet, He directly refers to himself as the CEO of Sierra as late as November 21st 1996.  To make matters even more unclear, the founders of Valve claim to have met Ken at Sierra's headquarters in November 1996 wherein he expressed interest in signing on their game-in-progress, Half Life, so that it could be published as a Sierra product.  He not long after did indeed sign on Half Life, and in a December 1996 interview talked about Sierra's future product direction as if he were CEO. 
Even more confusing is that he still contributed to Sierra's InterAction Magazine via his "Inside View" column until the Summer 1997--approximately a year after Sierra had been sold, and a press release from May 1997 regarding Half Life's debut at E3 '97 refers to him as Sierra's CEO and includes comments from him.  However in a late 1997 interview reflecting on what the year 1997 had been like at Sierra and what 1998 held for the company, he claimed he had not been in control of Sierra since July 1996 ; He has stuck to this claim ever since.
Ken was worked with Sierra as an unofficial Product Strategy Advisor and was employed by CUC as Vice Chairman and Member of the Office of the President until November 1997, when he quit to found Worldstream Communications, Inc. with ex-Sierra head of R&D, Jerry Bowerman. He served as Worldstream's CEO from November 1997 until October 2000, and has since been retired.
Ken was was given the (more honorary than actual) title of 'Executive Producer' on many of Sierra's products between the late 1980s and the early 1990s.
- Mystery House (1980)
- Wizard and the Princess (1980)
- Mission Asteroid (1980)
- Ulysses and the Golden Fleece (1981)
- Threshold (1981)
- Cranston Manor (1982)
- Time Zone (1982)
- King's Quest (1984)
- King's Quest II: Romancing the Throne (1985, Game Logic)
- Space Quest: The Sarien Encounter (1986)
- The Black Cauldron (1986, Programming)
- Police Quest: In Persuit of the Death Angel (AGI) (1987, Programming)
- Leisure Suit Larry in the Land of the Lounge Lizards (1987)
- 3-D Helicopter Simulator (1987)
- King's Quest III: To Heir Is Human (1987, Key Grip)
- Silpheed (1988)
- Police Quest II: The Vengeance (1988)
- King's Quest I: Quest for the Crown (1989)
- Quest for Glory II: Trial by Fire (1990)
- King's Quest V: Absence Makes the Heart Go Yonder (1990)
- Space Quest IV: Vohaul's Revenge (1991)
- Thexder (1987, thanks)
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