This book contains the papers of the Internal Combustion Engines: Performance fuel economy and emissions conference, in the IMechE bi-annual series, held on the 29th and 30th November 2011. The internal combustion engine is produced in tens of millions per year for applications as the power unit of choice in transport and other sectors. It continues to meet both needs and challenges through improvements and innovations in technology and advances from the latest research. These papers set out to meet the challenges of internal combustion engines, which are greater than ever. How can engineers reduce both CO2 emissions and the dependence on oil-derivate fossil fuels? How will they meet the future, more stringent constraints on gaseous and particulate material emissions as set by EU, North American and Japanese regulations? How will technology developments enhance performance and shape the next generation of designs? This conference looks closely at developments for personal transport applications, though many of the drivers of change apply to light and heavy duty, on and off highway, transport and other sectors.