OBJECTIVES: To determine the frequency and geographical distribution of children falling from a height in London and to suggest possible causes and preventative measures. METHODS: All relevant cases attended by the Helicopter Emergency Medical Service (HEMS) in a three and a half year period were reviewed and the locations related to the boroughs. The rates, per 1,000 resident children, were compared with socioeconomic indices for the boroughs concerned. In addition, a survey was undertaken of window fittings and maintenance in high rise flats close to one particular incident. RESULTS: A total of 90 incidents were attended involving 91 patients (64 male, 27 female) of whom five died. HEMS attends approximately one third of incidents involving serious trauma. In the study period the maximum frequency was 0.2 fallers per 1,000 resident children, occurring in three boroughs. In three boroughs there were no fallers. There was no overlap in socioeconomic indices between the five boroughs with the highest fall rates and the five with the lowest. The building survey found a high incidence of faulty window catches, a slow response rate for repair, and a lack of safety advice for residents. CONCLUSIONS: The frequency of falling is related to urban deprivation, poor maintenance, and lack of safety information. A combination of regulation and targeted education could substantially decrease deaths and injuries in children from this cause.