A total of 93 bipolar patients admitted in the 1940s were divided into those who received convulsive therapy and those who did not. Clinically, the two groups were similar. Those who received convulsive therapy were discharged back home more frequently, indicating the efficacy of the treatment. Those who received convulsive therapy showed more episodes, both manias and depressions, in the course of their illnesses. The reason for this difference in course of illness is not known, but deserves further exploration. The explanation may involve either biological factors or social circumstances related to a successful treatment outcome.