Civilization

Civilization, Advanced Civilization, p.n. 1. multi-player board game published by Avalon Hill; Advanced Civilization is an expansion set. 2. a series of computer strategy games, designed by Sid Meier and published by Microprose, based upon the Avalon Hill board game; a networked version, CivNET, is also produced. [GJ1]
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Addendum: The story of Civ is a little complex. The original board game was produced in 1980 by a company in Britain and picked up by Avalon Hill in '81. The game had a couple of expansions in 1988 and a pseudo-sequel in 1996 called Age of Renaissance (if people thought Civ was complex, AOR is a holy terror, though it claims to be shorter.) Acquired along with AH's other properties in 1998 by Hasbro when AH went under, Civ has not had a re-release in the U.S. since. 
The biggest possibility of why it hasn't been reprinted is because of a little computer game published by Sid Meier in 1991, named (get ready for it) Civilization. Meier had often claimed he didn't draw off of the board game for his game, though in other interviews he contradicts this statement as well as coworkers recalling that he owned a copy of it. Further evidence could also be that he computer game's full name is "Sid Meier's Civilization", possibly a way to get around copyright hangups. 
The real irony came in 2002 when Eagle Games (announced to be reprinted by Fantasy Flight games sometime by 2011) produced Sid Meier's Civilization: The Board Game, which drew all of its mechanics from the computer games instead of the original board game.