A considerable number of depressive patients do not respond to or remit during pharmacotherapeutical or psychotherapeutical interventions resulting in an increasing interest in non-pharmacological strategies to treat affective disorders. Electroconvulsive therapy (ECT) dates back to the beginning of modern biologic psychiatry and ongoing research has successfully improved efficacy in addition to safety while reducing side effects. Double-blind, randomized, controlled trials have shown powerful interactions between electrode placement (right unilateral, bifrontal, bitemporal) and dosage (relative to seizure threshold) in the efficacy and side effects of ECT. This review aims to summarize current research data on the mechanism of action, efficacy, and recent advances in ECT technique.