It is generally accepted that electroconvulsive therapy (ECT) is an effective treatment of major depressive episodes in patients with both unipolar and bipolar affective disorders (1). Yet, repeated relapse of depression occurs in some patients, even with vigorous maintenance therapy on antidepressant drugs (2-4). This often necessitates rehospitalization for ECT. In past decades, several authors suggested that periodic outpatient ECT was efficacious as a maintenance therapy (5-7). Recently, maintenance ECT was recommended by Fink (8), and Maletzky (9), but barely mentioned in two reviews (10,11), and discouraged in another (12) . However, a recent nationwide survey has disclosed that such therapy is widely practiced (13)
