This document discusses various theories and concepts related to managing organizational change. It begins by introducing some key change theorists like Kurt Lewin and his three step model of change involving unfreezing, moving, and refreezing. It also discusses different approaches to change like planned and emergent change. The document then explores sources of resistance to change at the individual and organizational level. Finally, it provides strategies for change agents to address and overcome resistance like communication, involving stakeholders, and viewing resistance positively.