The last ten years of research and clinical trials has emphasised the association between diabetes and hypertension. In type II diabetes >70% have associated hypertension according to criteria of >140/80 mmHg. In the majority of patients no secondary cause will be elicited, but recent data have described a higher prevalence of secondary causes in hypertensive patients than previously suspected. A review of secondary causes (hyperparathyropdism, Cushing's, phaeochromacytoma, acromegaly, hyperaldosteronism, thyrotoxicosis, and renal artery stenosis) will be undertaken including investigations and outcome. Renal artery stenosis and primary aldosteronism pose a particular problem in the diabetic hypertensive population. Controversial issues in management of hypertension in diabetic subjects will be outlined including: 1) Are investigations for secondary causes worthwhile? 2) Role of home and ambulatory blood pressure monitoring? 3) Can we ignore diastolic pressure? 4) Blood pressure target achievement? 5) Choice of anti-hypertensive agent – ACE inhibition always? - adoption of the polypill? 6) Trial data still needed?