This report offers a review of literature from various sources on the impacts of the production and use of liquid biofuels, which are used mainly in the transport sector. In 2009, Campbell and Doswald (2009) published a review similar to this one, focusing on the biodiversity impacts of biofuels, on behalf of UNEP-WCMC. This report reflects on the progress made since that review. This report has three main objectives: to identify key gaps in the existing literature about the social and environmental impacts of biofuels, with a special focus on biodiversity impacts; to develop a synopsis of the existing literature related to the sustainability of biofuel production; and to develope recommendations to address the gaps, in collaboration with IUCN.