AbstractThis paper shows the use of a multicriteria decision aid (outranking methodology) in resolving the problem of choice among industrial options against the pollution caused by vinyl chloride releases into the atmosphere. This carcinogenic substance is a basic product in the manufacture of plastics. The paper presents first a historical analysis of the choices made by industry since 1974 and the various studies that helped to rationalize these choices. It then suggests a modelling of the decision-making problem coherent with its actual complexity. Finally, it develops an operational method which will measure the impact of the implementation of pollution control options, and proposes solutions for different types of installation given the preferences of industry and those of public authorities.