All of the employees (n=9,457) in the 10 adult State prisons of a southwestern State received a Quality of Work Life questionnaire in June 1999 as part of the State's effort to assess employee perceptions of prison organizational climate. A total of 5,540 employees (58.6 percent) returned a usable questionnaire. Of these respondents, 3,794 classified themselves as correctional officers; and 703 classified themselves as treatment personnel. Two dependent variables were indicators of workplace stress. "Job stress" assessed the extent to which staff perceived feelings of tension and anger as a result of their work; "health" factors were used as the more objective measure of stress-related mental and physical disorders. Independent variables, which the literature has suggested as impacting workplace stress, pertained to role problems, organizational support, quality of supervision, coworker support, intrinsic rewards, environmental safety, and security level. The findings indicate that working in the correctional environment is equally stressful for both occupational groups, with no significant difference in the reported stress levels between correctional officers and treatment personnel. Variable role problems was the single most robust predictor of job stress for both occupational groups. 3 tables, 8 notes, 77 references, and appended environmental correlates scale items