Reorganization Planning is the strategic discipline of redesigning an organization's structure, reallocating roles, and managing the transition. It involves analyzing current organizational effectiveness, designing a target structure aligned with strategy, planning the transition sequentially, and communicating changes to minimize disruption. Reorganization differs from general change management in its focus on structural redesign rather than process change. Practitioners work with executives, HR, and teams to design structures, plan transitions, define new roles, and support people through uncertainty. The work blends organizational psychology, operations, and strategic planning.