This chapter analyzes how agricultural elites in Brazil converted economic weight into durable leverage inside Congress. It traces the shift from defensive reactions to land reform toward the deliberate accumulation of institutional power through the cross-party Bancada Ruralista (Frente Parlamentar da Agropecuária), aided by open-list PR, party fragmentation, and federal malapportionment. Original data show the caucus’s size (roughly a third of the Chamber, peaking above 40%) and its geography: a dynamic core from the South/Center-West joined by a decisive contingent from the North/Northeast (“agribusiness + coronelismo”). Multivariate models (1998–2010) link the number of ruralist deputies elected by state to agriculture’s value added and the intensity of land occupations, while industrial scale is not predictive. The chapter documents control of institutional levers—committee seats and leaderships, especially in CAPADR—seniority and reelection advantages, and campaign-finance patterns concentrated in agribusiness donors. It also shows that prior leadership in producer associations and personal economic stakes strongly predict core appointments, evidencing a legislative arena porous to organized sectoral interests. Together, these findings explain a cohesive ruralist bloc transformed sectoral organization into veto and agenda power over agricultural policy.