The purpose of this book is to provide a global vision on the biomethanisation of solid waste. It addresses the basic knowledge of biomethanisation, its field of application and its technical and technological aspects. It is through its environmental impacts and its added value to the energy sector and the target audience that this document draws its importance. The writing of this book is based on the university level, particularly students at the bachelor, engineer and master's levels in chemical process engineering, food process engineering, environmental engineering, energy engineering and renewable energies. This book can also serve as a reference document for the various industrialists, particularly those in the agri-food sector who will have to make strategic choices to manage the solid waste from their plants, as well as farmers who can benefit from agricultural waste.