Preliminary to a description of five change decisions made by New York City municipal government, rules of political practice as they affect change are discussed briefly, a simple taxonomy of organizational change is illustrated from municipal experience, and differences between the public and private sectors that either facilitate or hinder change are identified. An inductive method is used to describe five municipal changes in the areas of organization, education, labor relations, air pollution, and model cities, and then to analyze the processes through which the changes occurred.