In this project we used structural equation method to analyze the data collected during the period of re-engineering in hospitals in Ontario 1995 to 1997. We want to understand how organizational change affect the well being of the staff of large teaching hospital. Two main models were considered in this project: cross-sectional models and longitudinal models for the data collected in 1995 and 1997. We tested six models for each year's data in cross-sectional model, effect-indicator, cause-indicator and mixed-indicator were used in both standard and non-standard models. We explored standard model with effect-indicators in our longitudinal case. The study was carried by SAS software program. We demonstrated an important association of job stressors with psychological outcomes of hospital staff directly and indirectly via interference. Decision-making capacity was associated with psychological outcomes in the opposite direction. Similar results were concluded from longitudinal model. The limitation was discussed. / Thesis / Master of Science (MS)