The ecology of tactical overlap

Does sharing protest tactics influence the trajectory of protest activities among social movements? Focusing on the New Social Movements (NSMs), the authors apply concepts that have proven useful in the study of organizations. These concepts suggest that legitimation and competition processes influence both the upward and downward trajectories of protest. The sharing of tactics is specified in terms of increased overlap in the tactical repertoire of social movements composing a given cohort. A tactical overlap index is calculated between women's protest activities and activities generated by all other New Social Movements in West Germany, from 1953 through 1990. Results suggest that tactical overlap has a nonmonotonic effect on levels of protest activity generated by the West German women's movement.