The establishment of an area of freedom, security and justice is one of the key objectives of the Treaty of Amsterdam. Measures to harmonize criminal law as well as measures in the field of police and judicial cooperation in criminal matters are an integral part of the strategy by which to attain this objective. On the basis of the conclusions of the European Council meeting at Tampere (1999), it is obvious that measures are needed so as to guarantee the real mutual recognition of judicial decisions in criminal matters, including the pretrial decisions, and to guarantee the free circulation of criminal evidence. The original Corpus Juris study (1997) had elaborated a number of guiding principles in relation to the protection of the financial interests of the European Union within the framework of the European Judicial Space, including the European Public Prosecutor. This follow-up to the Corpus Juris study aims to analyse the feasibility of the Corpus Juris in relation to the legislation of the Member States and also to analyse the horizontal and vertical cooperation in the Member States. The publication of the follow-up study consists of four volumes. Volume I includes a final synthesis, with a new version of the Corpus Juris (Corpus Juris 2000), and syntheses on the feasibility of the Corpus Juris (draft of 1997) in relation to the legislation of the Member States. Volumes II and III include the 15 national reports concerning the 35 articles of the Corpus Juris (1997 draft). Volume IV relates only to questions concerning horizontal and vertical co-operation. The study was carried out in 1998-1999 upon the request of the European Parliament and the Anti-Fraud Office, OLAF, by researchers from the Association of European Lawyers for the Protection of the Financial Interests of the European Union.