In a randomized trial three ways of increasing rates of cervical screening were compared for women attending a family medicine center. Working from computerized medical records, 1,587 women aged 18 to 35 years who were overdue for a screening test were included in the study. In a control group, no formal method was used to encourage patients to attend for screening, and 13.7 percent obtained a test within the trial year. In one intervention group the physician was issued a message identifying those women visiting the center for a routine appointment who were due for screening; 16.1 percent were screened. Sending a letter to patients in a second group yielded a 25.9 percent compliance rate. In a third group the practice nurse called patients on the telephone to advise them to obtain the test, and 20.0 percent complied. Reminders issued to the physician provide a low-cost, opportunistic approach to reach women who happen to visit the practice, but this approach should be supplemented by telephoning or sending a letter to those women who do not attend regularly.