11 patients with atheromatous renovascular hypertension had a history of multiple episodes of pulmonary oedema. 7 had stenosis of both renal arteries, 2 had stenosis of the artery to a solitary kidney, and 2 had unilateral stenosis with an intact contralateral kidney. Successful revascularisation (by angioplasty in 8, and surgery in 3) improved blood pressure and renal function, and virtually eliminated pulmonary oedema. In a second series of 55 consecutive patients with azotaemia and renovascular hypertension, pulmonary oedema occurred in 13 (23%). Blood pressure and renal function were not significant predictors of pulmonary oedema, but coronary heart disease and bilateral (vs unilateral) renal artery stenosis were. Bilateral renal artery stenosis may be a specific and treatable predisposing factor to pulmonary oedema in azotaemic hypertensive patients.