As a preliminary to evaluating the introduction of a primary care emergency centre in Midlothian, information was recorded about 2,236 out-of-hours contacts made with eight general practices in the ten weeks before the centre opened. The overall rate of calls was estimated at 265 cells per 1,000 patients per year, with 63% of calls resulting in a home visit, 8% in the patient being seen at the surgery and 29% in telephone advice only; 18% of the out-of-hours calls generated a night visit fee. Eighty-five per cent of patients who requested a home visit were seen by a doctor and 15% of patients contacting their general practitioner out of hours were referred to hospital, either for admission or for treatment in an accident and emergency department. Doctors classified 61% of the calls as necessary, 29% as unnecessary and were unsure about the need for 9% of calls.