A list patient system has been tried out among general practitioners in four Norwegian municipalities for a period of three years. For some of the doctors involved the introduction of such a system led to increased work load due to mismatch between the doctor's work capacity and the number of patients on his/her list. However, the experience from the process of establishing the list provided useful knowledge and showed ways of avoiding similar problems if the system is introduced on a national basis. Waiting time for consultation has been reduced, and access to the doctor by telephone has improved. The demand for emergency on call services has been reduced because the doctors are easier to reach during the day. Patients are satisfied with the system and would like to see it become permanent. Two thirds of the GPs involved in the experiment share this standpoint.