This document discusses four popular change management models used by organizations for IT projects: Lewin's three-stage model of unfreezing, changing, and refreezing; the McKinsey 7-S model which examines seven organizational facets; Kotter's eight-step model comprised of three phases; and the Kubler-Ross change curve which models the emotional reactions of employees to change. The models provide different approaches but generally emphasize the importance of preparing employees for changes and supporting them through the change process to ensure project success.