Abstract
The author give some information on the frequency with which loss of directional control occurred in accidents involving commercial vehicles during 1955-62 on roads near Slough and on the motorway M1 during 1961-62. In accidents in which only a commercial vehicle was concerned, the proportion involving loss of control was much greater than in other accidents. Taking all types of accident into account, loss of control occurred about half as frequency in commercial vehicles as it did in cars.