A turn-based computer strategy game created by Sid Meier, Alpha Centauri is based on a hypothetical attempt by human beings to colonize a planet in the Alpha Centauri star system. It picks up where the game Sid Meier's Civilization II left off. According to the storyline of the game, the starship that carried the colonists to the planet suffered a malfunction shortly before arrival which resulted in a break-down of the chain of command. As a consequence, the once united colonists broke off into seven factions of varying ideologies to establish their respective colonies.
Within the game, the player assumes the role of one of the seven faction leaders and attempts to expand their colony and achieve victory. Players engage themselves in a race against the other factions, and are free to adopt any number of strategies in pursuit of their goal. Scientific discoveries within the game determine what technologies are available to particular factions, which in turn determines what facilities can build at their colony bases as well as what military units they can build. Confounding the competition among the human factions, it becomes quickly apparent that an indigenous form of life is also competing for resources. Also, while not unique in this regard, Alpha Centauri, is as an unusual civilization building game because it is open-ended and the parameters for victory can be set by the player; the player can choose to work toward a victory based on diplomacy, economics, conquest, or transcendance.
Alpha Centauri spawned one expansion pack called Alien Crossfire that featured seven new factions (two of which were alien) and multiple new technologies.