This comprehensive handbook is the revised version of the “BioFuel Technology Handbook” developed under the Biofuel Marketplace project, supported by the Intelligent Energy Europe Program of the European Commission. It was created in order to promote the production and use of biofuels and to inform politicians, decision makers, biofuel traders and all other relevant stakeholders about the state-of-the-art of biofuels and related technologies. Thereby, the large variety of feedstock types and different conversion technologies are described. Explanations about the most promising biofuels provide a basis to discuss about the manifold issues of biofuels. The impartial information given in this handbook further contributes to diminish existing barriers for the broad use of biofuels. Emphasis of this handbook is on first generation biofuels: bioethanol, biodiesel, pure plant oil1, and biomethane. However, it includes also second generation biofuels such as BtLfuels and bioethanol from lingo-cellulose as well as biohydrogen. The whole life cycle of biofuels is assessed under technical, economical, ecological, and social aspects. Characteristics and applications of biofuels for transport purposes are demonstrated and evaluated. This is completed by an assessment about the most recent studies on biofuel energy balances. GHG balances and sustainability aspects are important issues in the current discussion about biofuels. This handbook describes the current discussion about these issues and summarizes results of several studies. GHG calculation methods are presented and potential impacts of biofuel production characterized: deforestation of rainforests and wetlands, loss of biodiversity, water pollution, human health, child labor, and labor conditions. Finally, future developments in the biofuel sector are outlined. This includes discussions on 1st versus 2nd generation biofuels, integrated refining concepts and strategies for new vehicle technologies.