The third experiment will last 8 weeks and will enroll 12 individuals addicted to cocaine. A self-administration procedure designed to model relapse will be used to assess the effects of priming doses of cocaine on subsequent cocaine-taking behavior, alone and following aripiprazole treatment. Participants will be assigned to receive placebo for the first part of the study followed by aripiprazole for the remainder of the study or vice versa. During experimental sessions, participants will receive a specified amount of cocaine, which will act as the priming dose. Next, participants will choose between receiving either another similar dose of cocaine or money. This will be followed by a washout phase and then several more sampling-choice sessions with differing amounts of cocaine. Cocaine and aripiprazole doses will be determined by the results of the first experiment.