The claim of mutual benefits from trade liberalization has been particularly difficult to achieve in the case of trade in services. A recent contribution by Patrick Messerlin and Erik van der Marel suggests that if the US and the EU were to initiate negoatiations in this area, that would provide a useful catalyst to broader plurilateral negotiations with a manageable group of eight other major market participants.  Their table below indicates which services might be most amenable to this approach.  Given the large share of the market accounted for by the eight leading countries, the likelihood of inefficient diversion of service trade away from more efficient sources is less likely to occur.  

 Figure 1. Going plurilateral: How many countries make a critical mass?

Source: Messerlin and van der Marel (2009).