This article uses a simplified general equilibrium model to analyse the short and long run incidence of trade policy in Spain between 1978 and 1993. The incidence model is usually specified in an inter-industry framework, with increasing tariffs and either increasing or non-existent export subsidies. However, in this paper it is applied in a period of rapid liberalisation and with an intra-industry pattern of trade. The results, based on seasonal integration and cointegration techniques, show that, in the long run, the prices of exportables relative to non-tradables followed the fall in prices of import-competing goods. Hence, the effect of the liberalization process that took place in Spain during this period was precisely the intended one - that is to say, the enhancement of the competitiveness of the tradable sector as a whole. The slow reaction on the part of suppliers in shifting production from importables to exportables resulted in a certain gap between relative prices of tradables only in the short-run. In the end, the effect of trade policy was to create incentives for the reallocation of resources to the production of non-tradables.Spanish Trade Policy, Incidence Of Protection, Opening-UP Of Markets,