Enforcement of the European System of Financial Supervision (ESFS) has undergone a three-step process over time, leading it to a current networked configuration of powers and tasks between the EU and the national competent authorities (NCAs). In light of this, this paper has a twofold aim. First, it analyses the actual configuration of enforcement mechanisms in the ESFS, arguing that different patterns emerge across the three branches (banks, securities markets and insurance): as governance becomes more complex in terms of number of actors and functions, verticalisation of enforcement increases. Second, by taking into account the three Italian competent authorities, it assesses the concrete changes occurred both in organisation and in perceived effectiveness, through quantitative data and qualitative surveys. It therefore argues that the more institutionalised and verticalised is the enforcement governance, the less reluctant will NCAs be to transfer shares of their enforcing powers to the EU level and to change their practices and organisational structures concretely, according to harmonisation requirements by the European supervisory authorities and the European Central Bank.