Mutual recognition of judicial decisions in European criminal law is ambitious idea—or more precisely—very ambitious idea. It permits decisions to move freely from one State to another. It fights against the ‘foreignity argument’, i.e. it avoids a judicial decision to be rejected in another State simply because of its alien origin. It is a key element for the development of judicial co-operation in criminal matters in the European Union. Its implementation is one of the main areas of European Union activity regarding criminal justice. Mutual recognition of judicial decisions originally started in 1960s and 1970s by the Council of Europe conventions desirous of developing international (European) co-operation in the field of criminal law. However, attempts to introduce mutual recognition in the area of criminal law have never been successful at European level. “New evolution” of the mutual recognition in criminal matters can be observed in the area of European Union criminal law. At the beginning of the Lisbon era the role of the mutual recognition in criminal matters has been highlighted. Criminal law is a relatively novel area of European Union action for which the Treaty of Lisbon sets a clear legal framework, which should focus primarily on mutual recognition (and the harmonisation of offences and sanctions for selected offences). Over the past years, we saw the introduction of mutual recognition legislative instruments (for example, the Framework Decision 2002/584/JHA on the European arrest warrant, the Framework Decision 2005/214/JHA on the mutual recognition of financial penalties, the Directive 2014/41/EU on the European investigation order), which focused on implementation of concrete mutual recognition measures (for example, the European arrest warrant, mutual recognition of financial penalties, the European investigation order).