This research was undertaken to find out the basic causes of accidents from accident records. For this program, the accident records of Carling Avenue of the City of Ottawa were examined as a sample. This examination revealed that the lack of good accident reporting criteria and incomplete information are responsible for not having a clear idea of the basic causes of accidents. A table of information is suggested which must be available for better understanding of accident causes. An accident reporting form is also suggested as the present accident reporting form is not adequate to evaluate and treat accident causation. The theory of a control chart method for finding the accident causative factors in terms of a and b errors is suggested. Finally, suggestions are made with respect to further investigation into the accident causation.