This chapter discusses the implementation of EU policies after they have been adopted. It is structured around three phases in the implementation process: legal implementation, practical implementation and monitoring implementation. Each of these phases takes place both at the EU-level and within member states, leading to a system of multi-level administration. Subsequent sections zoom in on each of the three phases. In relation to legal implementation, both transposition by member states and the adoption of delegated and implementing acts by the Commission are discussed, including the system of comitology. The section on practical implementation looks at areas in which EU institutions are the main implementers and discusses the general EU requirements for implementation by member states. The section on monitoring implementation includes an extensive discussion of (the procedural set-up and practical use of) the infringement procedure and preliminary rulings. The chapter ends with a discussion of the role of EU agencies and European regulatory networks in the implementation of EU policies, stressing the variation within and commonalities between these two types of structure.

This chapter deals with the penalty of day fines in Spanish criminal law, examined both from the perspective of its legal regulation and its practical implementation. Particular attention is paid to explaining a remarkable peculiarity of the way in which day fines are applied in Spanish judicial practice: routinely lawyers, prosecutors and judges pay only superficial attention to the indications of the Spanish Penal Code as to how the daily fees of this penalty should be calculated. Hypothetically, the sole criterion for setting the daily unit should be the overall financial situation of the convicted, including not only his regular personal income but also property and other assets, debts, other sources of income, family obligations and other personal circumstances. However, in practice, in the vast majority of cases certain routine quantities are used through a method that is halfway between custom and intuition. Therefore, it can be said that theday fines system in Spain represents, instead of a way to take wealth seriously, rather one of taking income lightly