A two-man team, consisting of a physician (G.A. Ryan) and an engineer (A. J. McLean), conducted an on-the-spot survey of injury-producing traffic accidents in the metropolitan area of Adelaide (Population 600.000). An injury-producing traffic accident was defined as one to which an ambulance was called. Four hundred eight accidents were attended between the hours of 10 a.m. and 11 p.m. over two periods, totalling 17 months, in 1963 and 1964. This represents a 12.3% sample of all such accidents which occurred in these periods.