This study, commissioned by the Policy Department for Citizens’ Rights and Constitutional Affairs at the request of the JURI Committee, looks into the challenges and possible improvements of administrative cooperation between Member States, as regards cross-border enforcement of administrative fines and recovery claims. Legal instruments to facilitate transnational cooperation are necessary. Also the terms ‘fine’ and ‘recovery claim’ are often subject to different definitions in the Member States. Framework Decision 2005/214/JHA works for offenses regulated therein. Measures to improve cooperation are allowed by Article 82(1) TFEU but administrative authorities are regularly not judicial authorities. Amendments can be based on Article 114(1) TFEU if they serve to supplement provisions on information, service and enforcement assistance.