The second volume provides the advanced teaching material for the lecture "Fundamentals of Electrical Engineering" and offers an insight into more modern, abstract theories and methods that are becoming increasingly important for engineers. The focus of the work is on network theory and the detailed derivation of the physical foundations. In accordance with the requirements of the university, the methods presented have a high degree of general applicability. They also form the basis for understanding more advanced courses. To familiarize oneself with the teaching material, it is advisable to solve the exercises listed at the end of the book. Sample solutions are provided. For the 5th edition, the content has been adapted to the latest developments in the field.