The 2014-20 European Structural and Investment Funds regulations include provisions which strengthen the legal framework for examining and handling complaints under the ESI Funds. For the first time, the regulations require EU Member States to provide effective arrangements for examining complaints under their ESI Fund programmes (in Article 74(3) of the Common Provisions Regulation). However, provisions on how such complaints should be dealt with remain vague. This article examines some of the elements such complaints handling systems should include, proposes an analytical framework to assess the effectiveness of such systems, and asks whether imposing more stringent requirements on Member State authorities in this area could further exacerbate the already contested administrative cost of implementing Cohesion policy.