This study examined whether the sex of physicians and patients affected the preventive care of middle-aged and older patients of family physicians. The charts of 61 male and 75 female patients older than 50 years, whose primary physicians were third-year family practice residents, were reviewed to determine whether tests to screen for colorectal, breast, and cervical cancer had been offered to them in the previous 18 months by their primary physicians. Male residents had offered rectal examinations significantly more frequently than female residents to male patients older than 70. Female residents had offered mammograms, pelvic exams, and Pap smears significantly more frequently to women older than 50 than had male residents. Female residents had significantly higher rates of offering pelvic exams and Pap smears to women between the ages of 50 and 70, but this difference was not significant for women over 70. There were no significant differences in the number of refusals by male or female patients to male or female residents. Results suggest that the sex and age of the patient and the sex of the physician may play a role in differential rates of cancer screening.