Interest in close binary stars continues to grow apace. Substantial fractions of the observing time on the International Ultraviolet Explorer and the various X-ray satellites have been devoted to extending our knowledge of a variety of interacting binaries. These, together with applications of novel ground-based techniques and the steady improvement of traditional methods, and developments in methods of analysis, have led to major advances in understanding of the properties and evolution of close binary stars.

Our Symposium Close Binary Stars held in Toronto, 7-10 August 1979, was attended by 170 participants from 26 countries and over 100 papers were presented. The proceedings have been published as IAU Symposium No. 88, Close Binary Stars: Observations and Interpretation, eds. M. Plavec, D.M. Popper and R.K. Ulrich; Reidel Publishing Co., 1980.