Traditionally, treatment in the emergency department is noted for brief doctor-patient encounters, fragmented service, and lack of follow-up care. This atmosphere can lead to patient dissatisfaction and may contribute to the high rate of noncompliance with discharge instructions and medications. To cope with this problem, a prospective study was designed to evaluate a telephone follow-up system and its effect on patient care and satisfaction. During a 1-month period, all emergency department charts were reviewed daily, and approximately 15% were selected for recontact. These charts were selected using a detailed list of 20 criteria developed by staff emergency physicians. Calls were made by an emergency department physician, nurse, or social worker on the day following the patient's visit. Calls were assigned to staff members (physician, nurse, social worker) on the basis of preestablished criteria within the spectrum of their expertise and training. We were able to reach 81% (229/281) of the patients selected for recontact. The purpose of these calls was to question patients about changes in clinical status, reinforce discharge instructions, and identify any patient complaints about treatment. An average of 1.6 calls were made to successfully contact each patient. The calls lasted an average of 70 seconds. Of the patients contacted 42% (97/229) required further clarification of their discharge instructions. The calls resulted in direct medical intervention in the majority of patients (6/7) who stated their clinical condition had worsened. Ninety-five percent of the patients questioned (112/118) felt that the call was useful.(ABSTRACT TRUNCATED AT 250 WORDS)