The azapirones are a relatively new class of psychotherapeutic drugs with both anxiolytic and antidepressant properties and a favorable benefit-to-risk ratio. They represent a significant advance in psychotherapeutic drug development. Buspirone, the only azapirone currently in clinical use, is a partial serotonin agonist with low abuse potential, no sedative effects, no cognitive or psychomotor impairment properties and no significant withdrawal symptoms. It is well-tolerated by elderly patients. Clinical indications for which buspirone is particularly appropriate are chronic anxiety and mixed anxiety/depression states. Buspirone has demonstrated some efficacy in the treatment of a broad range of other serotonin-related disorders.