OBJECTIVE To ascertain the contribution of general practitioners to hospital intrapartum care in 1988. METHODS Confidential postal questionnaire. METHODS All maternity units in England and Wales. METHODS Type of general practitioner unit (if any); number of bookings, transfers, and deliveries by general practitioners; participation of general practitioners in the policy and audit of the unit. RESULTS 277 (93%) of 297 units replied. Of 611,644 deliveries, 36,043 (5.9%) were under general practitioner care. In all, 228 units permitted general practitioners to book women under their sole care: 65 were isolated, 29 alongside, and 134 integrated general practitioner units. Alongside units had significantly more bookings (568), antenatal transfers (69), intrapartum transfers (86), and deliveries (387) compared with isolated units (185, 18, 16, and 125, respectively) and integrated units (106, 18, 18, and 52) (p less than 0.001 for all differences). The percentage of women booked by general practitioners transferred either before or during labour was independent of both the type of unit and the number of general practitioner bookings. General practitioners in consultant units were significantly less likely to attend meetings reviewing perinatal mortality (p less than 0.01), and these units were less likely to have any form of general practitioner-consultant liaison committee (p less than 0.001) compared with general practitioner units as a whole. Compared with those in isolated and alongside units, general practitioners in integrated units were less likely to have taken part in deciding the unit's booking policy (p less than 0.01) and consultants more likely to be the final determinant of whether a general practitioner should be permitted to practice within the unit (p less than 0.001). CONCLUSIONS Both the number of deliveries booked by general practitioners and the number of isolated general practitioner units have fallen. Transfer from general practitioner to consultant care was independent of the general practitioner unit's caseload or the type of unit. General practitioner units differ from consultant units in important ways and differ among themselves as well. Except in remote areas, alongside units may be the ideal type of unit to encourage general practitioners to continue to provide intrapartum care.