<p>In the United States and across the globe, democratic institutions are facing sustained threats, raising urgent questions about how resistance movements can organize and sustain collective action over long periods of time. In prior editorials, we have focused on providing strategies for individual behavior scientists to engage in nonviolent resistance. In this editorial, we expand that perspective to consider how behavior science can participate in the design, organization, and sustainability of resistance movements. Drawing from behavior analysis, behavioral systems analysis, culturo-behavioral systems science, and contextual behavior science, we examine how shared values, participation structures, leadership practices, and reinforcement systems can support long-term resistance efforts when terminal reinforcers are delayed and uncertain. We provide examples of how to create opportunities for participation along a continuum of risk levels, how psychological flexibility may contribute to committed action among participants, and structures that distribute leadership and reduce attrition. Research on resistance movements consistently shows that mobilization alone is insufficient. Durable change requires organization, reliable production of aggregate products, and sustained contact with selecting environments. We conceptualize resistance movements as behavioral systems that can be intentionally designed to increase participation, coordination, and persistence over time. As behavior scientists, we can contribute not only as researchers and consultants, but as participants who help design environments and organizations that make sustained collective action possible. The success of resistance movements is not a function of mobilization alone. It emerges when movements are intentionally designed to play the long game, cultivating the structures and practices necessary for sustained, adaptive, and enduring action.</p>