The document summarizes key aspects of organizational development (OD) and Kurt Lewin's contributions. OD aims to address organizations' evolving needs through collaboration between internal/external experts to help organizations become more effective for stakeholders. It is a deliberate, lifelong process using theories and techniques from behavioral sciences to increase organizations' viability and ability to manage change. Kurt Lewin is considered the founder of social psychology and pioneered the study of group dynamics and organizational development. He developed concepts like force field analysis, action research, and the three-stage change process of unfreezing, moving to a new level, and refreezing at the new level.