This article uses six propositions developed from the resource mobilization and political opportunity structure approaches to social movements in order to highlight the importance of external resources and political environment in explaining the emergence, development, and decline of the Unemployed Councils-the major organization of the unemployed workers movement of the 1930s. The analysis emphasizes the dominance of the Communist Party on the inner life of the Councils but notes both the important exceptions to that dominance and the social functions served by that dominance. The analysis also suggests that conflicts among elites opened up the political space for short-term political concessions on the local, state, and national levels. Because Council leaders did not perceive the changing political opportunities of the New Deal, however, they were unable to consolidate these concessions nor build stable organizations among the working class. These conclusions speak to several unresolved or problematic issues in both resource mobilization and political opportunity structure approaches.