Positing that the structure and environment of police organizations constrain police officer activities through intervening effects of police department policies, the authors examined variations in vehicle pursuit policies across a sample of 51 Illinois police departments. The sample included 30 municipal and 14 county police departments, 6 university police agencies, and the Illinois State Police. Questionnaires were mailed to each police agency to elicit information on vehicle pursuit policies and organizational characteristics. Results demonstrated substantial variations in vehicle pursuit policies and practices across police agencies and showed that organizational features were significantly related to vehicle pursuit policies and to police officer pursuit behavior. Vehicle pursuit policies tended to be more formalized and more restrictive in large police departments that had more elaborately developed structures. Formal written policies containing more explicit and extensive restrictions on vehicle pursuit behavior tended to occur in police departments with taller rank structures and stronger adherence to a paramilitary hierarchy. Organizational features and policy variables had an apparent effect on vehicle pursuit practices. Vehicle pursuits occurred more frequently in smaller, less formalized police departments. Vehicle pursuits were also more common in police departments with less explicitly developed policies and which viewed themselves as oriented primarily toward crime fighting rather than community service. The lack of specific vehicle pursuit training was striking. 35 references, 3 notes, and 5 tables