Blood pressure was evaluated in adult patients (n = 9) and children (n = 57) with nephrotic syndrome and minimal change glomerulonephritis (GN). Prior to steroid treatment in the edematous phase, hypertension was found in 78% of adults (BP greater than or equal to 140/90 mm Hg or antihypertensive treatment other than diuretics) and 95% of children (BP greater than 95 percentile of age). After complete remission, the prevalence of hypertension decreased to 33% in adults and 19% in children. In 21 children with early focal segmental glomerulosclerosis, the prevalence of hypertension (BP greater than 95th percentile) was 91% and 24% after complete remission. In 20 adult patients with membranous GN, the prevalence of hypertension in the edematous phase was 89% and 30% after complete or partial remission. It is concluded that, irrespective of age, hypertension is a common feature of the nephrotic syndrome unrelated to steroid therapy or renal failure.