Based on practical problems in mechanical engineering, the author develops in this book the fundamental concepts of non-smooth thermomechanics and introduces the necessary background material needed to deal with mechanics involving discontinuities and non-smooth constraints. From this point, powerful methods for the applied mathematician and the mechanical engineer are derived, and applied to numerous cases including collisions of deformable and non-deformable solids, shape memory alloys, damage of materials, soil freezing, supercooling and solid--liquid phase changes, to name but a few. This book will be of great value to both the researcher and practitioner, but it can also be used as an advanced text for students in civil and mechanical engineering.