Motor proteins are molecular machines that convert chemical energy from ATP hydrolysis into mechanical work, which powers cell motility. Over the last ten years, single-molecule techniques and structural studies have led to rapid progess in understanding how these biological motors operate. How do they move? How do they generate force? How much fuel do they consume, and with what efficiency? Mechanics of Motor Proteins and the Cytoskeleton brings these new findings together. This book is for biology, physics, and engineering students who want to learn about the principles of protein mechanics and how it applies to the morphology and motility of cells. Understanding how motors and the cytoskeleton operate requires mechanical concepts such as force, elasticity, damping, and work. Introductory physics textbooks address these concepts, yet they are concerned primarily with macroscopic systems, whose motions are qualitatively different from the highly damped, diffusive motion of individual molecules. Mechanics of Motor Proteins and the Cytoskeleton provides a physical foundation for molecular mechanics. Part I explains how small particles like proteins respond to mechanical, thermal, and chemical forces, Part II focuses on cytoskeletal filaments, and Part III focuses on motor proteins. The treatments are unified in the respect that they are organized around principles rather than proteins: chapters are centered on topics such as structure, chemistry, and mechanics, and different filaments or motors are discussed together.