Up to now, the customs union between the EU and Turkey has been a win-win situation: it allowed a continuous increase in mutual trade and contributed to commercial gains on both sides. But this productive collaboration may be approaching a turning point. New EU trade agreements, such as the Transatlantic Trade and Investment Partnership (TTIP), would be clearly disadvantageous for Turkey as a non-EU member. The customs union that has been so successful until now could turn into a one-way street for Ankara. Because of the customs union, Turkey would be forced to lower its duties on imports from new EU trade partners, like the USA. Since Ankara is not an EU member, however, the Turks could not expect equivalently lowered duties for their exports to these countries. One way out might be to expand the EU-Turkish customs union. That is the recommendation of experts at the Bertelsmann Stiftung, based on this study.