Since a reduction in fuel consumption will lead to reduction in vehicle emissions, automobile manufacturers are currently under pressure to produce more environmentally friendly vehicles. Vehicle fuel consumption and emission models are currently the primary tools for evaluating the regional impacts of transportation projects and for developing and evaluating new powertrains and new hardware in the field of Intelligent Transportation System (ITS). This book presents instantaneous and gear-shifting-based analytical models of fuel consumption and regulated exhaust emissions directly account for the individual vehicle characteristics and for the forces acting on the vehicle.