This study aims to analyze some relevant terminological issues in the context of the negotiations on electronic commerce that have been taking place at the WTO since 1998 to determine how the work of the institutional translator is conditioned during the negotiations of a multilateral international agreement. With the purpose of understanding the context of these negotiations, their legal specificities, and the political and socio-economic interests at stake, we will first examine how these negotiations have developed from their start until today. Then, using a corpus of negotiating proposals from WTO Members in English and another one containing the Spanish version of the same documents, we studied the evolution of the use and meaning in both languages of significant terms in the framework of these negotiations. The results revealed an important lack of terminological consistency between the English negotiating proposals of the different Members, which remains in the Spanish version of these documents. We conclude that the existence of terminological discrepancies during the negotiation of a multilateral agreement is the result of differences in both the conceptual perception and the interests of the countries involved. This considerably limits the institutional translator's room to maneuver in contexts of this nature and makes him or her tend to adhere to a literal translation of the original documents.