The implementation of a new Information Technology in an organization represents a significant change. Little research, however, has been conducted on the collective power of Information Technology acceptance and change management. The current research seeks to integrate a prominent model of technology acceptance and change management theory to develop an holistic approach to Information Technology implementation and acceptance. Using Davis' (1989) Technology Acceptance Model (TAM) (Attitude) and Beer, Eisenstat and Specter's (1990) six step model of change (Change), this three phase longitudinal case study examined the change management of the implementation of a new Information System within a statutory authority. Results from the current study show that the addition of the six step model (Change) adds appreciably to the TAM (Attitude) in the prediction of general service satisfaction and perceived implementation success. Findings also show the temporal salience of the factors of the six step model and the TAM in the prediction of these dependent variables. The current research supports previous work by Davis (1989) and Thompson, Higgins and Howell (1994) who stated that initially people are motivated to use an Information System by affect, but will in time be more concerned with usefulness as habit formation occurs. The current study found that during the pre-implementation phase, commitment through communication and vision are critical to the change process. However, as the change moves into the implementation phase, consensus becomes most important. The shift in factors salient during the change process is what the author refers to as the temporal progression proposition. Strengths and limitations of the current study and recommendations for future research are discussed.