Hyperlipidemia is a major risk factor for atherosclerosis and probably contributes to the increased cardiovascular mortality following renal transplantation. We studied the lipid profiles of 62 adults (29 males) with stable renal function (mean plasma creatinine 0.14 mmol/l, SD 0.07), 7 months to 21 years after renal transplantation. Fifteen patients (24%) were above the age- and sex-adjusted 95th percentile for total triglyceride and 10 (16%) for total cholesterol concentrations when compared with a local reference population. The most common lipoprotein abnormalities were type IIa (19%) and type lib (13%). Multiple regression analysis demonstrated that the use of diuretics and angiotensin-converting enzyme inhibitors were significant factors determining plasma triglyceride concentrations. There were significant bivariate associations between plasma triglyceride concentration and duration since transplantation, plasma creatinine concentration and the use of ciclosporin and diuretics. Duration since transplantation and ciclosporin use were significant factors determining lower plasma cholesterol concentrations. The use of ciclosporin and diuretics was associated with a significantly higher apolipoprotein (apo) B concentration. The cholesterol/HDL cholesterol risk ratio correlated poorly with the apo B/apo A-1 ratio. The value of these ratios as predictors of coronary artery disease need to be established in renal transplant recipients.