The EU is not yet a customs union in service trade like it is in goods trade. Different EU countries have varying trade policies with non-EU countries in services. This study looked at the EU's service trade offer in 2003 and found that there are still differences in national policies that prevent a complete customs union. These differences mainly affect labor flows. The researchers suggest that through multilateral trade negotiations, the EU could eventually become a customs union in service trade, similar to what happened with goods trade in the past.