On the second best optimality of tariffs in the presence of 'incentive schedules.' The ranking of alternative policy instruments for dealing with internal distor- tions in open economies has so far been made under the assumption that the tariff or subsidies rates are fixed at a certain level by the government and thus that the affected economic agents behave as subsidy or tariff 'takers.' This paper analyses some of the implications of tariffs or subsidies being implemented in the form of incentive schedules from which the affected economic agent can choose his preferred rate, provided some conditions associated with the use of that rate are satisfied. Politique douaniere et ce'dules incitatives: un optimum de 'second rang.' La defi- nition d'un ordre preferentiel dans les instruments de politique economique susceptibles de corriger les distortions internes dans les economies ouvertes s'est faite de fagon conventionnelle danis l'hypothese que les droits de douane ou les taux de subside sont fixes a un niveau donne par le gouvernement et qu'ils affec- tent donc le comportement des agents economiques comme des parametres exogenes. Ce memoire examine certaines consequences de l'utilisation de cedules incitatives de droits de douane ou de taux de subside auxquelles sont attachees certaines contraintes et conditions et entre lesquelles les agents economiques demeurent libre de choisir l'ensemble taux-contraintes prefere. Traditionally tariffs have been considered to be poor instruments for dealing with domestic distortions (Meade, 1955; Johnson, 1965; Bhagwati and Ramaswami, 1963). If the distortion is associated with the rate of output of the import-competing sector, standard analysis tells us that a tariff is a second best solution since it involves an undesired 'consumption cost' due to the higher price it implies for domestic consumers, and this cost can be avoided if a direct output subsidy on domestic production is used instead. Similarly, if the distortion is associated with the market for the factors used in the production of the import-competing good, a tariff is only third best since, in addition to the consumption cost, it favours the use of more of the factors of production whose markets are not distorted. All of the above is I am indebted to Jagdish Bhagwati, Ronald Findlay, H.G. Johnson, and the referee