Over the last two decades cold atoms have emerged as a most useful platform for exploring quantum science and quantum technology. Cooling, trapping and manipulating atomic systems require understanding of low energy collisions physics. The purpose of this book is to bridge the gap between graduate teaching in scattering theory, particularly atomic scattering, and the emergent fields of cold atoms and cold molecules. Although this book presents basics of collisions physics as applicable to different branches of physics and chemistry, it is written with a particular emphasis on the physics of low energy quantum collisions and its applications to cold atoms. Key Features: Pedagogic description of the topics will make this book suitable for graduate students taking courses on quantum scattering theory and cold atomic physics. Each chapter will have exercises and worked examples Emphasises applications of theory to current research topics in several inter-related areas. Incorporates numerical techniques. Self-contained, with appendices summarising related topics needed by students.