The purpose of this proposal is to request funds to support a the scientific meeting of the International Society for Research on Impulsivity (ISRI) to take place on November 10, 2005 at the Washington DC Capital Hilton hotel as a satellite meeting of the Society for Neuroscience. The theme of the meeting will be "Impulsivity and Substance Abuse: Premorbidity, Comorbidity and Consequences". There is a growing body of evidence that impulsivity is important in initiation and maintenance of substance use disorders (Jentch and Taylor, 1999, Moeller et al., 2001, Bechara et al., 2002); yet, there is significant disagreement among researchers and clinicians regarding the exact definition of impulsivity and how it should be measured (Moeller et al., 2001, Barratt, 1993). The goals of this meeting are: 1. To bring together neuroscientists, clinicians, and behavioral scientists to focus on the problem of impulsivity, especially as it relates to substance abuse. 2. To encourage trainees, women, minority and junior faculty to study the role of impulsivity in substance abuse and other disorders. 3. To disseminate the presentations and findings from the meeting through a peer reviewed publication and through the web site of the society, www.impulsivity.org. The meeting will have four sessions on key topics related to impulsivity and substance abuse chaired by distinguished scientists who have expertise in the respective areas: 1) Mechanisms of Impulsivity, Chaired by Ernest S. Barratt, Ph.D., 2) Impulsivity and Premorbidity for Substance Abuse, Chaired by Brit Af Klinteberg, Ph.D., 3) Impulsivity and Comorbidity for Substance Abuse, Chaired by Marc Potenza, M.D., Ph.D. and 4) Impulsivity and Consequences/Maintenance of Substance Abuse, Chaired by Antoine Bechara, Ph.D.. In addition, there will be a poster session which will target trainees and young investigators. Through all sessions, the planning committee will strive for a balance of attendance and participation from junior investigators, women, trainees, and underrepresented populations through travel awards for these groups.