The networked structures that compose the Council of the European Union (EU) reflect a diversity of governance practices. The Council is both intergovernmental heartland and transnational collective decision-maker, a hybrid institutional form with a distinct organizational culture and set of “inherited traditions.” One of the more distinctive traits is the preference to work by consensus rather than formal voting. Taking a “decentred” perspective, this analysis explores the Council’s evolution as a normative order, a social field geared to consensus-seeking practices and an internalized store of traditions. The analysis draws from anthropological network research, IR practice theory, and sociological institutionalism’s views on organizational culture. The potential payoff of such an eclectic conceptual scheme is a sharper understanding of how both formal and informal rules matter and a more fine-grained explanation for the variegated practices and historical turning points in the Council’s evolving decision-making culture. This is illustrated by showing how Council networks are “sub-societies” that can change over time, how social capital is a source of network power, how consensus practices reinvented QMV during the 1980s, and how the legacy status of “very important interest” claims ironically act to condition the consensus culture over time.