Research on contentious politics has long emphasized political opportunity structures as central determinants of mobilization. Yet empirical evidence—from opposite secular or religious radicals in Israel to the Notre-Dame-des-Landes encampment in France and British Climate Camps—shows that radical movements frequently sustain and widen contention precisely when formal political openings are closed. This paper develops the concept of societal opportunity structures to address this gap. Societal opportunities are openings embedded in the organization of society itself: cultural dispositions, communal infrastructures, local authority networks, social boundaries, and relational fields that facilitate collective action independent of, or in tension with, formal institutions.

Drawing on ethnographic data of opposite Israeli radical Left and radical Right groups (2017–2022) and comparative evidence from NDDL and Climate Camps, the paper identifies shared mechanisms through which activists perceive, activate, and transform societal opportunities. Across ideologically and institutionally diverse cases, activists engage in strategic identity work, narrative alignment, and tactical occupation of semi-autonomous social spaces to exploit societal openings, compensating for institutional constraint.

The paper formalizes a conceptual typology of societal opportunity structures and theorizes their relationship with political opportunity structures as analytically distinct but mutually influential. This framework explains how movements escalate contention under institutional closure, reconfigure repertoires of action, and anchor political engagement in extra-institutional arenas. By shifting analytical focus from the state to societal configurations, it advances comparative theories of mobilization, extra-institutional politics, and radical collective action in contemporary democracies.