Although the consumption of government-sponsored lotteries has grown considerably over the past 30 years, few researchers have considered the psychological motivations underlying lottery purchase behavior. The present research explicitly investigates this issue by examining not only the reported motives for playing the lottery, but the motives for not playing as well. Based on open-ended surveys of lottery-eligible individuals, a formal taxonomy of purchase and nonpurchase motivations is developed. Variations in lottery expenditures are examined with respect to the reported motivations, demonstrating the key role of nonpurchase motivations in understanding lottery consumption levels. Policy implications and avenues for future research are also discussed. © 1999 John Wiley & Sons, Inc.