One year's utilization of medical and hospital services by some 3,300 Canadian steelworkers and their families who belonged to a prepaid group practice plan has been compared with utilization by the families of fellow members of the same union Local whose care was provided by independently practicing physicians. Although the group practice had no financial incentive to economize on inpatient care, its rate of hospital utilization was lower by about a quarter. On comparing the frequency of different types of service rendered under the two systems, it appeared that the group practice placed somewhat greater emphasis on health protection against the investigation and treatment of disease, but utilization of both laboratory and radiologic services was certainly higher in the population served by the group practice.