This is the preliminary version of an article to be published as Chapter 2, International Sales Law: Contract, Principles & Practice by Larry A. DiMatteo (Editor), André Janssen (Editor), Ulrich Magnus (Editor), & Reiner Schulze (Editor)(Nomos Verlag, 2016). The first part of this chapter deals with the language of the contract, in particular problems among the parties involving documents written in a language not understood by one of the parties or by the forum of the dispute. The second part covers problems caused by the multilingual drafting and interpretation of the CISG (Convention on Contracts for the International Sales of Goods) text, written in six official languages and many additional unofficial translations.