Data for the study were collected in 1976 from patrol officers in 19 police departments, representing samples of unionized and nonunionized groups and varying in size, geographic location, and crimes per officer. Factors receiving the highest stress ratings involved organizational and management practices, notably nonparticipation in job decisions; frustration with court leniency; and repetition in work routines. Correlations between different job elements and strain measures, however, revealed other factors more influential as potential stress producers. Concerns about job security and role conflict were the most significantly associated with officer negative health and emotional states. In this context, freer discussion and interactions with police management and peers, counseling, and stress management training would be positive steps in controlling stress-related problems. Common problems were work-related low self-esteem, divorce (especially for officers married prior to joining the force), and musculoskeletal and gastrointestinal troubles. Responses indicate that family concern for an officer's safety heightens job-stress effects. Patrol officers from unionized departments tended to express higher stress levels than their nonunion counterparts, possibly because the unionized departments were from larger cities with more bureaucratic pressures and problems. Tables, over 60 references, the questionnaire, and the sampling plan are included.