Before discussing the effects of ethanol on voltage-dependent calcium channels it is important to consider the physiological roles of calcium channels in the central nervous system. Indeed, it is only in recent years that investigators have begun to recognize that numerous types of calcium channels exist, that their cellular and brain regional localizations may differ, and that activation of these channel types may initiate different cellular responses. It is important to state at the outset, however, that this area of research is still at an early stage and many important questions remain to be answered and several controversies need to be resolved. The details of these questions and controversies are beyond the scope of this review. However, an attempt will be made to highlight some of the key questions in order to allow for a timely perspective on those effects of ethanol that may be linked with alterations in calcium channel function.