Approximately 8% to 10% of pregnancies are complicated by hypertension. The disease, whether it first appears during gestation or was present prior to conception, puts both mother and baby at risk. The fetal risks include deathin utero, poor growth, and prematurity. The risks to the mother are more difficult to assess, but intracranial bleeding is the most common cause of death. This review examines some of the physiological changes that occur in normal pregnancy and defines the hypertensive disorders of pregnancy. The recent data regarding pharmacologic and nonpharmacologic therapies for the treatment of hypertension in pregnancy are discussed, and comments as to the prophylaxis of preeclampsia are noted.