The XVlllth General Assembly of the International Astronomical Union was held in Patras, Greece, from 17-26 August 1982. It was marked by the tragic death of the President of the IAU, Professor M.K.V. Bappu, on August 19, 1982. This sad event, without precedent in the history of the Union, posed serious problems to the organization of the General Assembly, which could only be overcome by the full collaboration of all members, the organizers, and the Executive Committee. A tribute to the memory of Prof. Bappu was paid during a plenary meeting on 23 August 1982. The full texts of the speeches are published in Chapter I of this . volume. The excellent scientific programme in Patras was organized by the Presidents of the 40 IAU Commissions and coordinated by the IAU General Secretary (1979-1982), Professor P.A. Wayman. The local arrangements were taken care of by Professor C. Goudas and his collaborators from the Patras University. Due to the unexpected withdrawal in 1979 of another invitation to host the 1982 IAU General Assembly, the organizers in Greece had less than two years available for the extensive preparations, and our hearty thanks are due to them for their persistent efforts, which made this General Assembly an outstanding success.

The General Assemblies of the International Astronomical Union are landmarks in the life of the world-wide astronomical community, as they review, at triennial intervals, the progress made in this scientific field, promulgate the most spect acular astronomical achievements, formulate scientific programmes for the years to come and, last but not least, deal with the administration and finances of the IAU. The Reports on Astronomy 1976, published as Transactions XVIA (in 3 volumes) before the XVlth General Assembly, are a synopsis of the work done in astronomy from 1973 to 1975. The volume "Highlights of Astronomy , as presented at the XVlth General As sembly of the IAU in Grenoble, 1976" includes some selected scientific topics, and will appear in the first half of 1977. Apart from the Invited Discourses and the Proceedings of the seven Joint Discussions, the Highlights volume No.4 con tairsthe proceedings of two Joint Commissions Meetings.

The early years include principally resolutions, with few reports.