The book "Collagen: Structure and Mechanics" offers a comprehensive introduction to the biological macromolecule collagen and its diverse applications in biomaterials and tissue engineering. It is aimed at students and postdoctoral researchers in the fields of materials science, (bio)engineering, physics, chemistry, and biology. Readers gain insights into the structure and mechanical behavior of Type I collagen as well as collagen-based tissues in vertebrates, covering all length scales from the molecular (nano) to the organic (macro) level. The book is clearly and pedagogically written and contains up-to-date knowledge about the hierarchical structure, mechanical properties, and an overview of deformation and reinforcement mechanisms. It serves as a valuable reference for new researchers in this field as well as a foundation for courses in interdisciplinary materials science.