Books in the International Astronomical Union Highlights series

It has become a tradition in the Union to publish the Invited Discourses and the Proceedings of the Joint Discussions held at a Gene ral Assembly in a separate volume entitled HIGHLIGHTS OF ASTRONOMY. Part (TI) contains the proceedings of the four Joint Discussions and one Joint Meeting related essentially to stars and the structure of our Galaxy.

The scientific meetings of the !AU are the !AU Symposia, !AU Colloquia, Regional Meetings in Astronomy held under the auspices of the !AU, the Commission Meetings, which may be Joint Meetings of Commissions, and !AU Joint Discussions.

It is the customary practice to report the major events of a General Assembly -the Invited Discourses, Joint Discussions and Joint Commission Meetings in Highlights of Astronomy.

It has become a tradition in the Union to publish the Invited Discourses and the Proceedings of the Joint Discussions held at a Gene ral Assembly in a separate volume entitled HIGHLIGHTS OF ASTRONOMY. Part (TI) contains the proceedings of the four Joint Discussions and one Joint Meeting related essentially to stars and the structure of our Galaxy.

It has become a tradition in the Union to publish the Invited Discourses and the Proceedings of the Joint Discussions held at a Gene ral Assembly in a separate volume entitled HIGHLIGHTS OF ASTRONOMY. Part (n) contains the proceedings of the four Joint Discussions and one Joint Meeting related essentially to stars and the structure of our Galaxy.

The present volume contains the texts of the three invited Di scourses and of the papers presented duri ng seven Joi nt Discussion Meetings and eight Joint Commission Meetings. The invited Discourses were arranged by the IAU Executive Committee and the Joint Discourses and Commission Meetings by the respective chairpersons.

This volume of the Highlights of Astronomy contains the Invited Discourses and the proceedings or summaries of Joint Discussions, Special Sessions, and Working Group Meetings held at the XIInd IAU General Assembly in August 1994 in The Hague.