This article analyses some of the difficulties of institutional modernisation based on a study of Brazilian port reform in the 1990s. It explains how and why Brazilian business managed to organise collective action for dramatic reform of the port structure and labour regime, but was unable to maintain the consensus to ensure full implementation. It emphasises how the formal rigidities and informal outcomes of the corporatist institutional structure hampered an efficient pace of modernisation. The analysis applies two complementary theoretical approaches, institutional analysis and the logic of collective action, to illuminate the evolution of Brazilian corporatism in the context of a more democratic society and open market economy.