In the world of legal science and criminology, the book “Definition of Crime”, created by a team of authors, becomes a real guide for those who seek to understand the deep mechanisms of legal assessment and investigation of criminal acts. This work is not just a textbook or a collection of theoretical provisions, but a lively, rich with practical examples and analytical reflections, revealing the essence of the concept of crime and its boundaries in modern society. The book “Definition of Crime” immerses the reader in the complex and multifaceted world of criminal law, offering a unique look at how the concept of crime is formed, what signs and criteria allow to qualify the act as a criminal one. The authors, united by rich experience in the field of criminology, judicial practice and legal theory, masterfully analyze historical and modern approaches to the definition of crime, showing how views on this issue have changed in different eras and in different legal systems. As a result, the reader receives not only a theoretical base, but also practical tools for analyzing and evaluating criminal acts. This book is especially relevant for law students, graduate students, faculty members, as well as practicing lawyers, investigators and judges who face issues of qualification and investigation of crimes on a daily basis. It will also be of interest to those who are engaged in criminalistics, legal policy or simply seek to expand their knowledge of what exactly makes an act criminal and what criteria allow law enforcement agencies and the judicial system to establish the fact of a crime. For readers interested in the issues of ethics, social responsibility and legal regulation, the “Definition of Crime” will open new horizons for understanding the mechanisms of legal influence on society. The book pays special attention to modern challenges and problems associated with the definition of crime in the context of rapid development of technology, globalization and the complexity of criminal schemes. The authors consider such topical topics as cybercrime, economic crimes, terrorism and crimes against the person, showing how the approach to their definition and investigation is changing. An important part of the book is the analysis of judicial practice and comments on key cases, which makes it not only a theoretical manual, but also a practical guide for specialists. The style of presentation is distinguished by clarity, logical harmony and a wealth of examples, which makes it easy to learn even complex concepts. The author's team, known for its publications in the field of criminal law, uses accessible language, avoiding excessive legal stupidity, while not losing scientific rigor. This work combines academic depth and practical focus, making it a valuable resource for anyone who wants to understand how the concept of crime is formed and implemented in modern law. If you are looking for a book that will help you understand the intricacies of the definition of a crime, understand its role in the criminal law system and learn how to analyze complex situations related to the qualification of acts, “Definition of a crime” will become an indispensable assistant for you. This book deserves the attention of not only specialists, but also those who appreciate the deep analysis, logical harmony and relevance of legal science. Its reading will open new horizons in understanding the legal framework for combating crime and strengthening the rule of law.