overlapping memberships contribute to social movement activity in a variety of ways. in many ways, one could say that do for movement organizations what interpersonal networks do for individual activists. first, they facilitate the circulation of information and therefore the speed of the decision-making process. this is essential as the speed of mobilization compensates at least in part for the lack of organization resources over which movement have control. in the absence of formal coordination among organizations, mobilization becomes possible through informal links among activists. persons working across organization also facilitate the development of shared representations of conflicts. among Vancouver activists there were different ways of framing the conflicts, one based on a political economy perspective, another based on an identity perspective, and a third based on a liberal perspective. the distribution of these frames varied depending on activists commitment to overlapping memberships those who acted as linkages between different movements and organizations were disproportionately close to a political-economy frame, whereas adopters of an identity frame were more inclined to concentrate on individual organization.