The state-of-the-art of acoustic source modelling of road vehicles has been reviewed. Extensive measurements and simulations have been carried out. The aim has been to identify and quantify all relevant parameters influencing the noise emission of road vehicles. The collected information has been used to construct a source model suitable to combine with point-to-point sound propagation theory to calculate day-evening-night weighted yearly average sound pressure levels of road traffic noise. Each vehicle category is represented by two point sources, each having a specified sound power having contributions from tyre/road (rolling) noise and propulsion noise. As a minimum 3 vehicle categories are used: Passenger cars, medium heavy and heavy vehicles. Additional categories are defined. The medium heavy vehicle has two axles and the heavy vehicle has 3 or more axles but corrections are made for the number of axles. All default data refer to a reference condition: constant speed, 20 °C and the average of DAC 0/11 and SMA 0/11 road surfaces. Deviations from these conditions are corrected for. Default data, one constant and one speed coefficient, for rolling noise are given for each frequency band, 25-10000 Hz, using a logarithmic speed dependence.