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On the basis of discrete choice and traffic modelling, it is proposed to determine what would be an optimal road pricing scheme for the Brussels-Capital Region. The impact of alternative schemes on congestion, the emission of pollutants and the use of other modes of transport is then quantified.With an optimal road pricing scheme (i.e. price being equal to marginal congestion cost) whenever and wherever, traffic inside the Brussels-Capital Region would decrease by about 13% during the morning peak. As of now, such a pricing scenario could not be reproduced at an acceptable cost level, given the technological constraints at play to allow for a variation of price according to space and time in a precise fashion. Still, this result makes it possible to compute a corresponding average price, be it according to distance (mileage charging) or duration (zone toll).Finally, it is highlighted that even with a zone toll of only 3 €/day (significantly lower than the optimal amount), traffic would diminish by about 11%.JEL classification : R480, R410, D620