Published in the Journal of Occupational and Environmental Medicine, the following study sought to determine whether the relationship between organizational climate and employee mental health is consistent or differs across four large hospitals, and whether organizational efficiency mediates this relationship. Participants completed validated measures of organizational climate variables (social climate, participatory management, goal clarity, and performance feedback), organizational efficiency, occupational stress, and mental health. Results indicated that organizational efficiency partially mediated relationships between organizational climate, occupational stress, and mental health, suggesting that a focus on improving both the psychosocial work environment and organizational efficiency might contribute to decreased employee stress, improved mental well-being, and organizational performance.