This is a very exciting period for basic discoveries in the field of neuroscience. We can begin to hope for the kinds of understanding that will give us medical insight into the causes and mechanisms of the addictions. Such knowledge may open the way for methods of prevention and treatment by means we can hardly imagine today. Tests for genetic vulnerability to addiction, so that prevention measures can be focused on those who would benefit most? Stimulation of the production of endogenous brain chemicals? Repair of genetic defects in peptide or receptor production? Immunizations? Long-term replacement therapies? Who knows? The next decade or two should see exciting developments leading to practical clinical applications in the field of addiction.