Objectives: To review the present status of electroconvulsive therapy (ECT), emphasising recent practice changes. Data sources: MEDLINE database for the years 1987-1998, supplemented by a manual search of relevant articles. Study selection criteria: Primary research on ECT related to clinical indications, electrical dose, electrode placement, cognitive side effects, maintenance treatment, and training. Data synthesis: The most common use of ECT remains the management of depressive disorders resistant to antidepressant medication, especially when speed of response is paramount. Cognitive side effects are minimised, without significantly compromising treatment efficacy, by the use of unilateral electrode placement at suprathreshold dose rather than bilateral electrode placement at threshold dose. Ictal electroencephaphogram characteristics of greater seizure intensity are more accurate markers of treatment efficacy than seizure duration. With adequate pre-anaesthetic investigation and modern anaesthetic practice, morbidity and mortality of ECT are minimal. Post-ECT maintenance drug therapy or ECT is essential to reduce the risk of illness recurrence. The significant advances in knowledge of effective administration of ECT have not been matched by improved training of practitioners. Conclusions: ECT retains an important place in the acute management of depression. However, the quality of evidence available is generally poor, so that trials of various aspects of ECT use are required, including comparison of its efficacy with that of the newer antidepressant drugs, further means by which cognitive disturbances can be minimised without compromising efficacy, and strategies to prevent relapse.