A model of occupational stress in hospital nurses was developed and tested. The model used measures of organizational climate, supervisor behavior, and work group relations as predictors of the quantity of role ambiguity perceived by nurses. Data were collected on 232 hospital nurses working in a rural community hospital affiliated with a medical school. Results confirmed the hypothesized structural model. Organizational climate, supervisor behavior, and work group relations directly influenced role perception. Increased role ambiguity led to decreased job satisfaction and increased perceived stress. The organizational environment directly influenced job stress. Occupational stress exerted a strong direct influence on the development of depressive symptoms in nurses.