Global concern for energy security and environmental protection has put great emphasis on the search for alternative energy sources. The generation of biofuels from biomass has attracted worldwide study and development as it has emerged as a very viable alternative energy source. The development of alternative energy sources has gained popularity due to the rising global demand for energy and the depletion of conventional fossil fuel stocks. Concerns about energy security have also been raised in emerging economies. Biofuels have a lot of potential in these areas. Furthermore, when compared to fossil fuels, they have a lower environmental impact. The book "Biofuels and Bioenergy: Environmental Sustainability and Climate Change Mitigation" discusses the advancement of biochemical and biological technologies in relation to the synthesis of alternative energy source. The technology involved, as well as developments in the field of alternative energy source production and related fields, such as biofuel, biodiesel and bioethanol production, are highlighted and discussed in this book. It has also been discussed how waste materials could be used as alternative.