The recommendations of the expert panel of the National Cholesterol Education Program (NCEP) have been endorsed by national medical organizations as standards for the detection and treatment of hypercholesterolemia, yet information on how these recommendations are being followed in primary care settings is limited. This study was done to determine how family physicians in four primary care clinics associated with a teaching hospital in a large southern city follow the NCEP guidelines. Of the total patient sample (N = 817), about 60% had at least one total serum cholesterol measurement. Patients in the younger age groups were less likely to have a cholesterol determination than older patients. Of those in the "self-pay" category only 33% had a cholesterol determination. Variability by clinic and provider type was also noted, with physician assistants showing the highest compliance with screening guidelines (75%), whereas only 43% of patients seen by family practice residents had a cholesterol measurement. Of patients who should have had a lipoprotein analysis, based on total serum cholesterol and risk factors, only 23% actually had a lipid profile. Our study and other similar ones point out that case finding varies considerably and that efforts to improve case finding need to continue.