The book "Electronic Structure and Magnetism of Complex Materials" offers a comprehensive analysis of recent advances in electronic structure theory and its application to magnetic materials. It highlights the microscopic aspects of magnetic materials and enables a first-principles approach to the study of technologically relevant magnetic substances. The authors, David J. Singh and Dimitrios A. Papaconstantopoulos, present a variety of topics in this specialized book, including the treatment of non-collinear magnetic systems, the role of orbital magnetism within band structure formalisms, and density functional approaches for magnons and spin excitations. The book is a valuable resource for researchers and students engaged in the theory and applications of magnetic materials in complex systems.