Preparation (forms, equipment, training, and planning) and the functions of traffic accident investigation first are examined. Processes then are described for finding informants and for initial and formal questioning of informants as a source of information about the accident, the driver and his condition, and the driving process. Information that can be obtained by the analysis of skidmarks, yawmarks, imprints, road scars, and debris also is detailed; methods of estimating vehicle stopping distances and speed are described. Vehicle identification, description, and damage classification are covered, as are procedures for examining vehicle lamps, tires, and wheel assemblies. Finally, the importance of the after-accident situation map for followup investigation is emphasized, and methods for producing and documenting the map are examined. Special attention is paid to methods of measurement at the scene, photography, and drafting the map. Sources, a list of exhibits (charts, tables, photographs, maps) and references are provided for each of the 13 topic sections. Index and glossary.