We study the dynamics of optimal trade policy in a model with costly inter-sectoral adjustment of labour, where migrants pay less than the marginal social cost of migration. If workers have rational expectations, a future tariff has an announcement effect on the current migration decision. If...

Optimal distortions for the agricultural sector are calculated taking as given distortions in the nonagricultural sector. The calculations use a general equilibrium model and assume that the sole criterion is economic efficiency. For most agricultural commodities, existing distortions should be...