The Energy Independence and Security Act of 2007 (EISA), significantly expanded the renewable fuel standard (RFS) established in the Energy Policy Act of 2005. The RFS requires the use of 9.0 billion gallons of renewable fuel in 2008, increasing to 36 billion gallons in 2002. EISA requires an increasing amount of the mandate be met with "advanced biofuels" -- biofuels produced from feedstocks other than corn starch and with 50% lower lifecycle greenhouse gas emissions than petroleum fuels. Within the advanced biofuel mandate, there are specific carve-outs for cellulosic biofuels and biomass-based diesel substitutes. This book focuses on the ongoing debate on the lifecycle emissions from biofuels, including finalised regulations by the state of California for a state low carbon fuel standard in January 2009 and the growing congressional interest in this topic.