United Nations Conference on Trade and Development

ii NOTE The purpose of this series of studies is to analyse policy issues and to stimulate discussions in the area of international trade and development. The series includes studies by UNCTAD staff, as well as by distinguished researchers from academia. In keeping with the objective of the series, authors are encouraged to express their own views, which do not necessarily reflect the views of the United Nations. The designations employed and the presentation of the material do not imply the expression of any opinion whatsoever on the part of the United Nations Secretariat concerning the legal status of any country, territory, city or area, or of its authorities, or concerning the delimitation of its frontiers or boundaries. Material in this publication may be freely quoted or reprinted, but acknowledgement is requested, together with a reference to the document number. It would be appreciated if a copy of the publication containing the quotation or reprint were sent to the UNCTAD secretariat