This study focuses on developing a new approach to seated work positions. It was conducted on 67 office workers who use the Video Display Terminal (VDT) as a major function of their working day. Muscle tension was measured by surface electromyography when subjects were asked to adopt four selected working postures. Pain was measured before and after ergonomic intervention on the Nordic scale, which was modified for this study. Performance was measured on timed typing tests. A psychosocial questionnaire was used to determine influences of job demands, and a diagnostic assessment was performed to determine symptoms and pre-existing musculoskeletal conditions. Furniture was used to place subjects in desired positions during the clinical testing sessions and the extended intervention period. The chair seat pan was adjusted to a forward tilt to promote a lordotic curve of the low back, resulting in an erect upper body and upright head position. The desk and keyboard were adjusted to the proper height for each worker. A neutral wrist position was obtained by lowering and tilting the keyboard away from the user. Results revealed muscle tension scores in the upper trapezius and forearm extensors were significantly reduced when the workers were placed with the head in a midline position, with forward-tilting seating and with use of a negative sloping keyboard tray. Subjects reported low pain scores at pretest so no changes were noted after intervention. Loss of control over job elements, lack of job satisfaction, and fear of job loss were related to an increase in muscle tension. Only fear of job loss correlated to increased pain levels. There was no relationship between any of the job demand factors and performance.