Change management involves preparing for, managing, and reinforcing organizational changes. It requires the involvement of project teams, senior leaders, managers, and employees. The three phases of change management are preparing for change by defining strategies and teams, managing change through implementation plans, and reinforcing change by collecting feedback and celebrating successes. The ADKAR model provides a framework for change involving awareness, desire, knowledge, ability, and reinforcement. Effective change management connects activities like communication and training to business results.