The purpose of this study was to determine outpatients' satisfaction towards waiting time in the Department of Family Medicine of a medical center. A self-administered questionnaire was used to collect information on the waiting time for a medical visit, satisfaction toward medical visit, and reasonable time for a medical visit as perceived by outpatient during the period from December 19 to December 24, 1994. The results showed that 81% of subjects were revisiting patients, and 59% of subjects made reservations for their visits. The average waiting time and consultation time for patients with a reservations were 40 minutes and 5.8 minutes, respectively, while for patients without a reservation were 80 minutes and 7.7 minutes, respectively. 52.6% adn 69.1% of patients were satisfied with the waiting time and consultation time, respectively. 69.1% and 49.6% of patients thought that 16 to 30 minutes and 6 to 10 minutes were reasonable waiting time and consultation time, respectively. The major areas of patients' dissatisfaction included: (1) unreasonable patient volume; (2) a long waiting time; (3) slow delivery of medical records for patients without reservation; and (4) inadequate services for waiting patients. Recommendations for systemic design include: (1) a reasonable patient volume; (2) a more accurate recommended arrival time for consultation; and (3) informing patients of the expected waiting time; (4) promoting patients to visit on time; (5) providing waiting patients with related services; and (6) improving the environment of waiting rooms.