Published online by Cambridge University Press: 01 January 2026
Scholarship on boundary crossing in organizations typically focuses on endogenous strategic decisions to broaden audiences and resource pools, rarely capturing exogenous shocks that initiate the process. Yet, rapid social change can also drive organizations to cross boundaries. Boundary crossing or adopting the issues, causes, and claims of other groups can lead organizations to reconfigure, returning to core questions determined during their founding about the problems they seek to address and who belongs in the group. In doing so, organizational trajectories change, producing lasting transformations or leading to disbanding. This study uses multi-sited participant observation and interviewing to examine the influence of Black Lives Matter on two social movement organizations, analyzing the internal organizational processes that determined and defined boundary crossing and the divergent outcomes for the participating organizations. This study is one of the first to depict the internal experience of interacting across movement boundaries.