This article argues that social democratic and orthodox Marxist conceptualizations of politics are unable to “engage in solidarity” with many new forms of Latin American popular politics. Such movements challenge the politics of representation, the market economy, and the state form by reinventing territorialized experiments in self-government, which politicize place, subjectivities, and social relations. Developing a critique of these frameworks of political analysis, this article argues that conceptual categories combining the insights of autonomist or open Marxism and poststructuralism and the critical reflections and theorizations by Latin America's newest social movements enable a deeper engagement with such movements. This critique challenges academics committed to progressive social change to reexamine long-held notions about the nature and agents of social transformation and the epistemological categories that orient our research. It argues that if we fail to do this, then we risk becoming gatekeepers of the status quo.