Although electroconvulsive therapy (ECT) was first introduced to treat schizophrenia in 1938, it is widely used for the treatment of various major psychiatric disorders, including depression. In western countries, its safety has been improved with the introduction of techniques such as succinylcholine muscle relaxation, barbiturate anesthesia, oxygenation and brief-pulse stimulation. Although the first use of ECT in Japan was reported in 1939, few modifications of the ECT technique have been made since then. From the 1980s, in collaboration with anesthesiologists, ECT with anesthesia and muscle relaxation (modified ECT) has been administered in numerous general hospitals. Moreover, brief-pulse ECT devices were approved in 2002. Rapid progress in ECT practices is expected in Japan. Before administering ECT, informed consent should be obtained from the patient, except when the patient lacks capacity to consent. The major problems in ECT are cognitive side effects and high relapse rates. Furthermore, its mechanisms of action are still unknown. These problems must be solved in the near future.