Existing perspectives suggest that waves of rural unrest arise as responses to economic and environmental shocks. We propose an integrated framework, grounded in the literature on interest group politics and state-society relations, to explain the dynamics of rural protests by commercial farmers and peasants in democracies during periods of disruptive and rapid change. Focusing empirically on South America during the 2000s agricultural boom, we argue that contentious collective action under democratic rule during shocks is a costly political strategy shaped by access to connections in formal policymaking arenas and the cohesiveness of organizations representing farmer and peasant interests. To substantiate our argument, we conduct within- and cross-case comparisons of Argentina and Paraguay, employing a mix of primary and secondary evidence, and incorporating shadow cases from Brazil and Bolivia.