Among the many factors that have contributed to the rapid growth of UK imports of manufactures over the last fifteen years or so, tariff reductions, both general and preferential, are usually mentioned as being one. Hitherto, however, the effect of all such reductions has not been quantified though some studies of the effect of EFTA membership on imports have been made. This article attempts to repair the omission by calculating the extent of the tariff cuts and by examining their effect on two broad groups of manufactures–semi-manufactures and finished goods.