Increasing technological sophistication in many countries and the resulting larger world trade has indicated a need to pay greater attention to the international aspects of user interfaces. Many American companies are approaching a situation where half of their sales are outside the United States, and companies in smaller countries often have a much larger proportion of their sales outside their own country. This means that software sales will increasingly depend on their international usability and not just their domestic usability. Seen from a user's perspective more than half of the world's software users will be using interfaces which were originally designed in a foreign country. Usability for this large market of users will depend upon increased awareness of the issues involved in designing user interfaces for international use. As the European community aims to establish the so-called Single Market by the end of 1992, international software will become even more important in that part of the world. And as if it wasn't hard enough to design user interfaces for use in Europe, there are a further set of problems connected with user interfaces for Asia.