Electroconvulsive therapy (ECT) is an efficient, safe and even life saving treatment for several psychiatric disorders, namely depressive disorder, bipolar disorder and schizophrenia. Many were the doubts with it utilization, namely until the 1980s. After that it became more accepted with the publication of guidelines for many international associations of Psychiatry. Even with the development of psychopharmacology, ECT is still used with very good results, namely with affective disorders. Nowadays it is used almost exclusive with refractory patients but many studies show its efficacy in all the phases of psychiatric disorders where is indicated. The authors' review, based on literature, the history, indications, mechanism of action, procedure and adverse effects of ECT. The recent development of many procedures of magnetic stimulation could put ECT as a secondary treatment but the efficacy of that technique in comparison with ECT is still to be demonstrated, and ECT remains the most efficient treatment of psychiatry disorders.