Relatively little is known about the sexual side-effects of psychotropic drugs, probably due to the taboos surrounding discussion of sexual matters. However, there is a growing interest in this topic. The antidepressants are probably the most widely studied class of psychotropic drug and evidence suggests that all commonly used classes are associated with some sexual side-effects. However, there may well be differences between the effects of different drugs in the same class. The study of sexual side-effects in bipolar patients taking mood stabilizers is complicated by the existence of numerous confounding variables and only limited data are currently available on the sexual side-effects of benzodiazepines and antipsychotics. It is also important to take into account a number of methodological considerations when interpreting data on the sexual side-effects of psychotropic drugs.