This working paper addresses two dimensions in which transnational or supranational regulatory regimes may be regarded as self-sufficient, providing some reasons, limits and pitfalls from such a tendency. The focus of both parts is on competition policy, which is of particular importance because of its transversal character: the fact that it can be applied in many if not all markets means that competition policy is a useful tool for market opening/integration and is likely to create conflicts with different policy objectives pursued in various market settings. Moreover, competition policy often acts as a trump on ordinary private law principles and can be used by administrative actors to substantially re-order private relationships. The first section focuses on the regulatory network and the idea of its self-sufficiency as a regulatory club for the self-enforcement of commonly agreed-upon norms independent of any formal mechanism for enforcement or dispute resolution within the network. As such, national regulators may develop obligations qua club members, distancing themselves from national communities. Yet the paper seeks to show that even informal enforcement requires mechanisms for making the actions of national administrations observable and characterisable. While mechanisms that perform that function have been observed in some EU networked regimes, these can be used either to enforce a hierarchical EU intrusion into national legal orders or to stimulate learning from divergent approaches stemming from persistent heterogeneity within the EU; it is an empirical research question to determine which is a better characterisation of the networked regulatory regimes. The second section focuses on self-sufficiency by way of a narrow definition of the policy mandate of legal and regulatory regimes, i.e. the idea of the instrumentalisation of a branch of the law for the achievement of a particular policy objective. This type of mandate definition can have a number of advantages: concentrating on a narrowly defined mandate can increase the likelihood of achieving it, it can allow for the proper sequencing of different policy tools where some objectives need to be prioritised and in a multi-level environment it can allow for the allocation of policy tools to different levels. Yet, by reference to the relationship between competition policy and social policy objectives, the second part highlights some of the risks involved in building such self-standing regimes, including the development of rationalities and institutional habits that are difficult to dislodge even in the face of absence of success in achieving (or better yet trading off) the myriad objectives of public policy.