IAU Transactions XXIIIB summarizes the work of the XXIIIrd General Assembly. The addresses given during the Inaugural and Closing Ceremonies are reproduced in Chapters I and III, respectively. The Proceedings of the two sessions of the General Assembly, including the Report of the Finance Committee, will be found in Chapter II. The Report of the Resolutions Committee and the Resolutions approved by the General Assembly are found in Chapter IV. The Accounts for 1994-1996 and other aspects of the administration of the Union are recorded in Chapter V, which constitutes the Report of the Executive Committee and thus provides the permanent record of the activities of the Union in the period 1994-1997. Chapter VI of this volume contains the reports of the Commission meetings in Kyoto, provided by the Commission Presidents. The Statutes, Bye-Laws and Working Rules of the Union as revised at the General Assembly are published in Chapter VII, while an updated version of the Rules for Scientific Meetings is given in Chapter VIII. Finally, Chapter IX contains lists of the countries adhering to the Union and of its approximately 8300 individual members, ordered by geographical location and commission membership as well as alphabetically (with full addresses). The IAU remains one of the few Scientific Unions in which a vigorous body of individual members contributes in a crucial way to the spirit and aims of the Union.