The main purpose of this thesis was to evaluate and test the Job Stress Survey (JSS, Spielberger, 1991; Spielberger & Vagg, 1999), a self-report instrument which assesses workplace stress. In the thesis a thorough evaluation is made of JSS scales and items, and the relations to health, particularly musculoskeletal complaints. The aim of Study I was to evaluate the factor structure and the psychometric properties of a Swedish version of the JSS. The instrument was distributed to medical service personal and metal industry workers (n=1186). Factor analyses demonstrated a good resemblance between the present version and the American original version. The results also showed that the internal consistencies, as well as the test-retest reliabilities of the scales are high, and the concurrent validity are good. Study II examined work-related stress measured by JSS for the subgroups of gender, industry workers and medical service personnel, and special attention was given to the problem of differential item functioning (DIF) on these subgroups. The main findings were that both gender and occupation has a substantial impact on specific sources of work-related stress assessed by JSS scales and individual items. The result of the DIF analyses showed no item bias in the gender subgroup, but for the occupational subgroups there where items showing DIF in two of the scales. These items do not jeopardize the conclusions made on scale level since the number of items showing DIF are too few to make an impact on the overall result on the different scales. In Study III the relation between self-reported stress and health, particularly musculoskeletal problems were examined longitudinally in two metal industry factories. Results showed high levels of stress and musculoskeletal complaints in these factories and significant and strong relationships between the JSS scales and musculoskeletal, as well as psychosocial ratings. Lack of Organizational Support was found to be more related to musculoskeletal pain than Job Pressure. Longitudinal differences were found between the factories and between different types of musculoskeletal complaints. The general conclusions from the studies are that the present version of JSS shows a good resemblance with the American original, and that JSS is a useful instrument for studying relationships between stress and health.