Fuel-efficiency devices such as retrofittable aerodynamic technologies, fuel-efficient tires, and auxiliary power units can effectively offset engine-efficiency losses resulting from the 2002 and 2007 Environment Canada and U.S. EPA emissions regulations, while reducing greenhouse gas (GHG) emissions significantly. To identify which fuel-saving devices are most effective, consistent, clear involvement from government is critical. If the industry is to quickly and effectively improve its GHG emissions, government must play a leadership role, a technical role, and a financial role. This report discusses how truck operators can reduce the fuel use and GHG emissions of their vehicles. Beginning with an explanation of end-use efficiency, we outline the major end-use opportunities on highway trucks and then discuss the financial and environmental benefits of the efficiencies. Estimates show that if the entire Canadian fleet of 294,000 Class-8 trucks were to adopt a full package of energy-efficiency technologies, Canadian truck owners and operators would save 4.1 billion litres of fuel and reduce emissions by 11,500,000 tonnes of GHG each year. This is equivalent to taking 64,000 Class-8 trucks off the road or taking 2.6 million cars off the road.