Understanding factors that alter the effect of alcohol in biological systems has been an area of active investigation for several decades. Recently, it has become clear that age is one of the most salient factors influencing how both acute and chronic alcohol exposure alters behavioral function. The following book chapter discusses how alcohol produces differential effects in adolescent animals in comparison to adult and aged (i.e., older) animals. Furthermore, where possible, relevant research identifying possible brain mechanisms mediating the differential effects of alcohol will be discussed. Finally, we highlight a small number of studies where sex and age of the subject interact to modify cognitive impairments produced by alcohol. We conclude that much work still needs to be done to fully understand how age, sex, and alcohol interact to produce the wide range of effects caused by consumption of the drug.