EU Council Framework Decision 2009/829/JHA of 23 October 2009. on the application between Member States of the principle of reciprocity” is a unique and important study that immerses the reader in the complex world of European legislation and law enforcement practice. This work, created by a team of authors, is not only a legal document, but also an in-depth analysis of the principles underlying cooperation between the Member States of the European Union. The book focuses on the framework decision adopted by the EU Council, which concerns the application of the principle of mutual recognition in criminal cases. It is a principle that implies that decisions taken by one member state should be recognized and enforced by other member states. This approach greatly simplifies law enforcement and promotes more effective interaction between countries, which is especially relevant in the context of globalization and increasing transnational crime. The book will be of interest to both specialists in the field of law and students of law faculties, as well as anyone interested in issues of international law and European integration . It will become an indispensable source of information for lawyers working in the field of criminal law, as well as for researchers and analysts dealing with law enforcement in the context of the EU. Professionals working in law enforcement will also find in this publication many useful ideas and practical recommendations. The topics raised in the book cover a wide range of issues, including the principles of justice, human rights, criminal justice cooperation and the impact of European legislation on national legal systems. The authors emphasize the importance of mutual recognition as a mechanism for promoting more effective and speedy justice, which in turn increases citizens’ confidence in the legal systems of their countries and the EU as a whole. The style of presentation in the book is clear and accessible, which allows the reader to easily assimilate complex legal concepts. The authors use many examples and illustrations, which makes the material more clear and understandable. This is especially important for those who are just beginning to get acquainted with the issues of European law .. The book also contains an extensive bibliography, which allows readers to delve into the study of the topic and find additional sources of information. In the context of other well-known works, the work of the collective of authors can be compared with the works of authors such as Jean-Louis Benjamin and Klaus-Herd Geisel, who also explore issues of European law and law enforcement. The EU Council Framework Decision 2009/829/JHA stands out for its practical focus and relevance, making it an indispensable tool for legal professionals. EU Council Framework Decision 2009/829/JHA of 23 October 2009. on the application of the principle of reciprocity between Member States” is not just a legal document, but an important contribution to the development of legal science and practice It opens new horizons for understanding the mechanisms of interaction between states within the European Union and emphasizes the importance of the principle of mutual recognition in the modern world. Readers interested in law, politics and international relations will find in this book many valuable ideas and inspirations for further research.