The work "Criminal Law - Concepts and Institutions of the General Part" deals with the General Part of the new Penal Code (Law 4619/2019) which came into force on 1.7.2019 and is updated until Law 4637/2019. It is a concise and well-documented presentation of the General Part of Substantive Criminal Law, the theoretical analysis of which is combined with numerous practical examples that help in better understanding of the text. The method of processing the content of the book is based on the numbering of all its paragraphs, with margin numbers, as well as on the correlation of these numbers among themselves. In this way, the study of the book becomes easier, as the discussed topics are interconnected, so that the reader has immediate and quick access to previous or subsequent concepts. The edition is complemented by an alphabetical index. It is a user-friendly theoretical and practical aid for lawyers, judges, and students of criminal law.