We compared current practice with the National Cholesterol Education Program (NCEP) guidelines for the detection and evaluation of hypercholesterolemia and analyzed the association of various patient and provider factors with screening. Using a retrospective medical records review of 1,000 randomly selected patients between the ages of 18 and 70 in a university-based general internal medicine practice--faculty, residents (categorical and primary care), and nurse practitioners--we found that 80% of patients were screened for hypercholesterolemia. Patients older than 35 were more likely to be screened than younger patients (87% versus 77%; P = .001), and, among younger patients, nonwhites were less likely to be screened than whites (58% versus 77%; P = .0001). Lipoprotein analysis was done in 60% of the 235 patients in whom it was indicated; older patients were significantly more likely to have these measurements. Among patients taking medications for hypercholesterolemia, 92% had lipoprotein analyses done beforehand. No differences were detected in screening by provider characteristics. We conclude that providers in our practice are appropriately aggressive in screening high-risk patients for hypercholesterolemia. The finding that young whites are screened much more often than nonwhites was surprising. Finally, although there is a high rate of screening overall, many patients with elevated cholesterol levels are not appropriately classified as to their low-density-lipoprotein levels.