"Notwithstanding their name, defects turn out to be, as Selinger's book shows, very useful in a variety of fields, particularly in the study of liquid crystals, magnets, and other ordered matter systems. The topic has become increasingly important, as shown by the more than twofold increase in the number of papers dealing with topological defects listed by Web of Science in the last ten years, making the book certainly timely. Selinger has managed to introduce the subject in a way that is accessible to a wide audience of students and researchers, starting with simple physical examples, relatively straightforward maths, and helpful illustrations to arrive at complex and often unfamiliar concepts, such as Skyrmions and Hopfions. I appreciate the book's pragmatic yet elegant approach and have no hesitation in recommending it." (Claudio Zannoni, Emeritus Professor of Physical Chemistry, University of Bologna, Italy) "In this elegant, concise book, Jonathan Selinger allows readers to reap insights gained during a distinguished career focused on understanding liquid crystals, magnets and other complex materials. With a minimum of fancy mathematics and a maximum of physical intuition (rendered in part through beautiful illustrations), he leads the reader with lucid prose to a basic understanding of the essential features of topological defects and solitons in condensed matter physics." (David R. Nelson, Arthur K.

Solomon Professor, Harvard University) "In his book Introduction to Topological Defects and Solitons Jonathan Selinger brings the reader from the basic notions concerning topological defects and solitons all the way to the more sophisticated ones of "hedgehogs," "skirmions," "hopfions," etc. They are exposed with clarity, avoiding unnecessary difficulties, but pointing at all aspects of the fascinating domain of topological singularities and solitons in magnetic systems, liquid crystals and also superconductors on occasion. Upon reading the book, one has the impression of listening to the master explaining at the blackboard the concepts with the use of well-designed drawings and well-chosen words. Without any doubts, this book will be useful to our community and beyond." (Jacques Prost, Institut Curie, France).