Although electroconvulsive therapy (ECT) has generally been reserved for patients refractory to other forms of treatment, its use as a first-line treatment, prior to the use of other biologic approaches, has occasionally been mentioned in the literature on the treatment of affective disorders and, when indicated, can prove rapidly effective and even life saving. The present study retrospectively reviewed 27 cases treated over the span of a decade in which ECT was chosen as the first treatment of an affective episode. In none of these cases was antidepressant medication or other biologic approaches used for the current episode. A clinical global rating scale was employed to measure improvement. Although the majority of such patients were treated with ECT first based upon the severity of their depressive illness, 13 received ECT because of their obtunded condition and these patients, initially diagnosed as catatonic on admission, were suspected of having a bipolar condition, as revealed on their discharge diagnosis. In addition, ECT was recommended preferentially in 4 patients because they were pregnant and in another 4 because it had worked well in the past; an additional patient received ECT first because of his fragile medical condition. Almost all patients recovered and none suffered serious adverse effects. Sample case histories are provided along with tentative guidelines for the consideration of first-line use of ECT in clinically difficult cases.