Despite the large number of patients with chronic hypertension, hypertensive emergencies constitute a relatively rare medical emergency. However, marked and sudden elevation in blood pressure may represent an immediate threat to life. Prompt reduction of blood pressure is essential and may be life saving. Overtreatment, on the other hand, can prove equally injurious to the patient. It is the purpose of this review to characterize situations in which rapid reduction of blood pressure is required, to outline general medical management and specific use of antihypertensive medications required to control blood pressure, and finally to discuss special treatment problems in hypertensive emergencies.