Interest regarding the challenge-hindrance occupational stress model has increased in recent years, however its theoretical foundation has not been tested. Drawing from the transactional theory of stress, this study tests the assumptions made in past research (1) that workload and responsibility are appraised as challenges and role ambiguity and role conflict are appraised as hindrances, and (2) that these appraisals mediate the relationship between these stressors and outcomes (i.e., strains, job dissatisfaction, and turnover intentions). For a sample of 479 employees, we found that although workload, role ambiguity, and role conflict could be appraised primarily as challenges or hindrances, they could also simultaneously be perceived as being both to varying degrees. Support was also found for a model in which primary appraisal partially mediated the stressor-outcome relationship. (Contains 2 tables and 2 figures.)