 Impulsivity has been described as the cognitive inability to delay gratification, a failure to inhibit behavioral action or acting without forethought about consequences. Impulsivity has also been seen as a personality trait characterized by risk-taking or sensation seeking behavior. Pathological gamblers demonstrate aspects of impulsivity; they act without thinking, have difficult inhibiting urges to gamble and desire immediate gratification. The goal of this project is to clarify which components of impulsivity are associated with pathological gambling. Non-treatment seeking, pathological gamblers and controls will be recruited from the community and local casinos. Each participant will be administered a battery of tests that represent different operational definitions of impulsivity. 