From a practical point of view, the well-proven antisuicidal and anti-aggressive effects of lithium are of utmost importance for a rational, safe and economical treatment of patients with affective disorders. Regular lithium long-term treatment reduces the otherwise 2- to 3-fold increased mortality of untreated patients with severe affective disorders down to the level of the general population. This is mainly due to the reduced suicide risk. Many international studies have confirmed this fascinating property of lithium which so far has not been demonstrated with comparable evidence for any other psychotropic compound. The antisuicidal effects of lithium might possibly be related to its anti-aggressive effects which have been shown in various species, populations and settings, such as animals, inhabitants of nursing homes for the elderly, mentally handicapped subjects, children and adolescents with hyperactive, hostile and aggressive behavior, and particularly in hyperaggressive inmates of correction units and prisons.