This article proposes a new approach to hegemony, recast as a tool to capture the power of ideas at the systemic level. Hegemony is conceptualized as a condition in which a set of ideas is accepted by political actors with conflicting interests and as the outcome of a process of discursive interaction. Three types of ideational contestation are distinguished—confrontation, configuration and consistency: hegemony emerges as contestation shifts between these forms. This approach is elaborated through an analysis of key affirmative action policy debates in Malaysia between 1955 and 2010. We show that hegemony depends in part upon the content of ideas; that once ideas become hegemonic they are less liable to radical change; and that ideational hegemony constrains not just ‘subaltern’ groups but also powerful actors. In Malaysia we show the establishment of a hegemonic set of ideas effectively ‘locked in’ dominant elites, even as they sought to change affirmative action policy.