The volume is intended as a source document for use by students in the administration of justice, police officers, engineers, administrators, court attorneys, insurance investigators, corporate directors, and transportation safety directors. A historical overview of transportation and traffic problems is followed by definitions of basic transportation terms and a system for classifying collisions. Guidelines for conducting an investigation of a collision cover the role of the investigator, management of the collision scene, preparing a report of the investigation, and common reasons for collisions. Advice is also given for identifying drinking drivers, providing the necessary tests, arresting the drinking driver, and handling the incarceration and testimony in court. Additional discussions cover the physiological and psychological factors that affect driving, wet weather driving and hydroplaning, and the transportation of hazardous materials. Information is also provided on formulae for reconstructing collisions in both miles per hour and kilometers per hour; completing reports required to document arrests, collisions, and reconstructions; gathering and preserving evidence; and traffic law enforcement tactics and techniques. Photographs, diagrams, forms, discussion questions, appendixes presenting mathematical tables, an index, and 17 references are provided.