Book excerpt: With the establishment of the WTO, trade in services became part of the world trade order. Volume 6 is dedicated to these rather recent developments. It covers the core agreement, the General Agreement on Trade in Services (GATS) with annexes, as well as the additional instruments , which have been adopted later on to govern the liberalization in specific sectors. Those are the Understanding on Commitments in Financial Services, the Second Protocol on Financial Services, the Third Protocol on the Movement of Natural Persons, the Fourth Protocol on Basic Telecommunications and the Fifth Protocol, which contains further rules for financial services. This volume will be a valuable reference tool for the WTO community as a whole, as well as for professionals and researchers, who deal with one of the sectors concerned, e.g. financial services and telecommunications. Furthermore, it is highly relevant in view of those sectors, which are the subject of ongoing liberalization efforts or earmarked for future negotiations, namely accounting, legal services, transport, tourism, environmental services, legal and educational services.