This article presents the proceedings of a symposium at the 2001 RSA Meeting in Montreal, Canada. The organizers and chairs were William J. McBride and Ting-Kai Li. The presentations were (1) Metabolism of ethanol in the brain and the behavioral consequences, by Richard A. Deitrich and Sergey Zimatkin; (2) Catalase production of acetaldehyde as a possible mediator of the psychopharmacological effects of ethanol, by Brian R. Smith; (3) The reinforcing actions of acetaldehyde in the ventral tegmental area, by Zachary A. Rodd-Henricks; and (4) Salsolinol and alcohol addiction, by William J. McBride.