A group of patients in a haemodialysis and renal transplant programme have been assessed for the frequency of lipid abnormalities. Hypercholesterolaemia was not a significant problem amongst haemodialysis patients, but mild hypercholesterolaemia was common amonst transplant patients. Mild hypertriglyceridaemia was a feature of both haemodialysis and transplant patients. Irrespective of initial lipid values, each patient was advised to undertake dietary fat modification for a period of eight months. There was a small significant lowering of plasma triglyceride values in the haemodialysis group. It is concluded that major lipid abnormalities are not a feature of this group and that the return for dietary fat modification is small, although occasional individual patients may warran hypolipidaemic therapy.