To assess whether nephrologists perceive disparities between the skills learned during fellowship training and those necessary for clinical subspecialty practice, we surveyed the perception of board-certified American nephrologists regarding the effectiveness of their clinical training. A questionnaire was sent to all Diplomates of the American Board of Internal Medicine in the subspecialty of Nephrology who successfully passed the qualifying examination in 1974, 1980, and 1986, regarding the effectiveness of academic instruction within the clinical fellowship program as regards traditional academic subject matter, patient management, performance of procedures, and interpretation of laboratory data. Questionnaires were returned by 42.1%. Although respondents were generally satisfied with training in academic nephrologic subject matter, dissatisfaction with training in pediatric nephrology, transplant immunology, nephrolithiasis, nutrition, and renal function and disease in pregnancy was evident. Training was thought to be ineffective in theoretical and practical aspects of management of end-stage renal disease. In addition, respondents were dissatisfied with the effectiveness of their training in interpretation of radiologic tests and procedures such as gaining access to the circulation. More recently trained nephrologists were dissatisfied with training in outpatient management and interpretation of radiographic tests. Differences between perceptions of older and younger nephrologists were most marked regarding their preparation for gaining access to the circulation, interpretation of intravenous pyelography, and training for continuous ambulatory peritoneal dialysis (CAPD). To prepare fellows in training for the exigencies of clinical practice. Nephrology training programs will have to emphasize the teaching of the cognitive and manual bases of performing procedures, and provide more outpatient experience for trainees.(ABSTRACT TRUNCATED AT 250 WORDS)