Relations between business, state, and civil society in Latin America are conventionally discussed in antagonistic or hierarchical terms. This article challenges this position, developing a qualitative case study tracing the activities of an informal network of Brazilian businesspersons that, over the last three decades, promoted an agenda of sustainability, transparency, and civil society participation. Drawing from concepts in social movement theory, it is argued that a dynamic movement-like behaviour combining civil activism, organisational entrepreneurship, and fluid political alignment, allowed the group to establish lasting collaborative alliances with core actors in Brazilian democratic politics, and access relevant elite and policy-making circles.