The paper analyzes the development of the women's movement, indicating how this particular movement empirically documents the theoretical suppositions of a sociologically defined social movement. A social movement is defined as "a group venture extended beyond a local community or a single event and involving a systematic effort to inaugurate changes in thought, behavior, and social relationships." In the first half of the paper, the author describes integral parts in the formation of a social movement, including the role of a communications network, organizational form, leadership, and goals. The women's movement has been able to grow due to the effective use of modern, mass media. There are two branches, the reform or "women's rights" branch, and the radical branch. Within the paper, the National Organization for Women (NOW) is discussed as an example of how the reform branch works within the system toward reforming social and political institutions. The radical branch, which has rejected a formal organizational style, is more liberal. Various crises are reviewed which prompted formation of specific women's movement groups on national, state, and local levels. Ten common goals are identified, including revision of divorce and alimony laws, Equal Rights Amendment (ERA) passage, and change in educational and political systems to assist and admit women. (AV)