This book gives an overview of current progress of topological phases in structured classical magnetism and acts as an important reference for designing novel topological spintronic devices. The text explores basic topological models and provides readers with an overall understanding of topological phases in magnetic systems. References to important original literature are included throughout as well as extended reading. The concepts of topological magnonic devices proposed in the book encourage researchers to design real topological spintronic devices. The methods for studying topological phases in this book can extend to other systems, which enables readers to find new topological materials. The key audiences for this text include researchers in the field of topological magnetism and research institutes.