OBJECTIVE: To discover how often hospital discharge summaries were available to physicians seeing patients for follow-up visits after hospitalization. DESIGN: Cohort study. SETTING: Teaching hospital in Ottawa, Ont. PARTICIPANTS: We studied 792 patients discharged from an internal medicine service after treatment for acute illness. We determined when and by which physician each patient was seen during the first 6 months after discharge. We also determined the date each patient's discharge summary was printed and the physicians to whom it was sent. We confirmed that summaries were received by means of a survey or by telephoning physicians' offices. Patients were observed for 6 months or until they were readmitted to hospital. MAIN OUTCOME MEASURES: Proportion of follow-up visits to physicians for which discharge summaries were available. RESULTS: During the observation period, patients made 6619 visits (median six per patient, interquartile range [IQR] 2 to 9) to 914 different physicians (median three per patient, IQR 2 to 4). Discharge summaries were available for only 996 (15%) visits. Summaries were available for only 65 initial visits (8.2%); no summaries were available for any visit for 542 (68.4%) patients. Summaries were most commonly unavailable because they were not generated in time for follow-up visits (20.0%) or were not sent to follow-up physicians (50.8%). CONCLUSION: At our institution, discharge summaries often did not get to physicians seeing patients after discharge from hospital.