Recent advances in neuroscience have made it possible to investigate the pathophysiology of alcoholism at a cellular and molecular level. Evidence indicates that ethanol affects hormone- and neurotransmitter-activated signal transduction, leading to short-term changes in regulation of cellular functions and long-term changes in gene expression. Such changes in the brain probably underlie many of the acute and chronic neurological events in alcoholism. In addition, genetic vulnerability also plays a role in alcoholism and, perhaps, in alcoholic medical disorders.