How is it that regardless of the reforms introduced by the Lisbon Treaty to better contain European integration in areas of core state powers, ‘competence creep’ can continue? What is the underlying cause? And why is it problematic? This article proposes answers to these questions through a systematic (re‐)conceptualization of the problem of ‘competence creep’, arguing that it results from the cross‐cutting governance that is the legal Leitmotif of European integration as well as from ‘two‐level games’ of national governments, and that it is problematic from the viewpoint of democratic legitimacy. However, it argues that the one form of competence creep that is most commonly understood as the core problem, and on which most reforms have focused, namely indirect legislation in areas of Member State competence, is actually the least worrying type of covert integration; negative and parallel integration, soft law and co‐ordination are all far more problematic.