"The Atomic Nucleus as a Relativistic System" is a specialized book that explores the role of relativity theory in nuclear physics. Since the 1970s, interest in the relativistic treatment of the atomic nucleus has grown, leading to a multitude of scientific papers. This book provides a comprehensive overview of significant developments in this field and presents relativistic theory as an effective tool for describing the structure and reactions of nuclei. It is aimed at advanced students and researchers, offering both an explanation of the underlying relativistic concepts and a comparison of theoretical predictions with experimental results. The authors, Lev N. Savushkin and Hiroshi Toki, contribute their expertise to make the complex relationships between relativity and nuclear physics understandable.