The effects of complete withdrawal of steroid therapy on blood pressure and other clinical variables were studied in 58 renal transplant recipients subsequently maintained on azathioprine and cyclosporine; 76% of the patients were hypertensive prior to withdrawal of steroids. Cessation of steroids was accompanied by a significant decrease in mean arterial blood pressure and by a reduction in the number of required antihypertensive medications; however, changes in blood pressure were variable among individual patients. Previously normotensive patients exhibited little further decline in blood pressure. Multivariate analysis of the entire cohort of patients showed that the reduction in blood pressure accompanying steroid withdrawal was directly related to the prior severity of hypertension and inversely related to the dose of cyclosporine. We conclude that steroids play an important role in the pathogenesis of posttransplant hypertension in the majority of renal transplant recipients. Withdrawal of steroids generally is accompanied by reduction in blood pressure, but the benefit is greatest in previously hypertensive patients receiving relatively low doses of cyclosporine.