The paper develops two synthetic measures at the HS-10 level to depict effective market access for a country receiving preferential access and applies these to the market access ASEAN members would receive following the implementation of an FTA with the EU. First, the measures show that current effective market access for ASEAN EBA members is cut in half by the preferences granted by the EU to countries that compete with these countries in the EU markets. Second, the measures show that about one-quarter of the preferential margin under the proposed FTA for EBA members would be lost as a result of preferential access granted to ASEAN GSP members. Third, disaggregated estimates of the restrictiveness of rules of origin confirm that rules are more restrictive for products with higher preferential margins and that ASEAN countries usually face tougher rules of origin in the EU because of the composition of their exports.