The religious imagination of the Greeks, Robert Garland observes, was populated by divine beings whose goodwill could not be counted upon, and worshipers faced a heavy burden of choice among innumerable deities to whom they might offer their devotion. These deities--and Athenian polytheism itself--remained in constant flux as cults successively came into favor and waned. Examining the means through which the Athenians established and marketed cults, this handsomely illustrated book is the first to illuminate the full range of motives--political and economic, as well as spiritual--that prompted them to introduce new gods.