This book will attempt to provide an account of knowledge on biomass available for biomass-based biorefineries. Its focuses on understanding the recalcitrance of biomass and how it limits the overall conversion efficiency. It also gives an insight what are different conventional approaches available for pretreatment and hydrolysis of the biomass. The chapters deals with highlights how enzymes can be a powerhouse and play pioneering roles in biomass valorization. The book will also throw light on how technical aspects of thermochemical conversion strategies such as pyrolysis, gasification, organosolv methods for the generation of value-added materials such as high-quality bio-oil, biochars, and biobased chemicals. These high-value compounds can be put to widespread application in biofuel, biocatalyst, waste bioremediation (heavy metal removal), air purification and effluent treatment applications. The book will provide literature on the limitations of already existing technologies and provide prospects of each technology. This book is of interest to teachers, researchers, bioenergy scientists, capacity builders, and policymakers. Also, the book serves as additional reading material for undergraduate and graduate students of energy studies, chemical engineering, biotechnology, and environmental sciences. National and international energy scientists and policymakers will also find this to be a useful read.