Self-control is a promising concept for consumer research, and self-control failure may be an important cause of impulsive purchasing. Three causes of self-control failure are described. First, conflicting goals and standards undermine control, such as when the goal of feeling better immediately conflicts with the goal of saving money. Second, failure to keep track of (monitor) one's own behavior renders control difficult. Third, self-control depends on a resource that operates like strength or energy, and depletion of this resource makes self-control less effective. Trait differences in self-control predict many behaviors. Implications for theory and research in consumer behavior are discussed.