Road Speed Limiters were developed to improve safety and the environment by controlling the top speed of vehicles, thus reducing serious accidents and pollution. The basic function of the system is to limit the maximum speed of a vehicle to a preset level while the throttle (accelerator) pedal is fully depressed, without a noticeable variation in the speed. In many cases this restriction in the top speed has shown to dramatically reduce the amount of fuel used when compared to higher top speeds. The reduction of fuel costs is an important part of most businesses. The reduction of carbon dioxide emissions is also becoming a major factor for many companies. When a reduction in fuel consumption is recorded, a reduction in carbon dioxide emissions is also apparent. For companies with an active ‘Green policy’, the introduction of speed limiters onto fleet vehicles can be a major step forward in reducing their carbon footprint. The increase in fuel economy is not the only benefit however, as the operating RPM is much lower at 70 mph as opposed to 80+ mph the engine and vehicle component wear can also be reduced.