The observational evidence for the existence of black holes has grown significantly over recent decades. Stellar-mass black holes are detected as X-ray sources in binary systems, while supermassive black holes, with masses more than a million times the mass of the Sun, lurk in the nuclei of galaxies. These proceedings provide a useful and up-to-date overview of the observations of black holes in binaries, in the center of the Milky Way, and in the nuclei of galaxies, presented by leading expert astronomers. Special attention is given to the formation (including the recent evidence from gamma-ray bursts), physical properties, and demographics of black holes.

Observational and Theoretical Issues of Interacting Binaries was the topic of the 22nd Advanced Course of the Swiss Society for Astrophysics and Astronomy. It was the first time that binary systems were the center of attention of our course. The established concept and organisation of the Advanced Course has been retained: three scientists, all acknowledged experts in their respective fields, were each invited to give nine one-hour lectures within the period of a week. The Advanced Course took place from April 6 to 11, 1992, at Les Diablerets, a charming resort in the Swiss alps. The high level of the lectures, the international background of the 65 participants, including many young students, and the beauty of the surroundings all contributed to the success of the course. The lecture notes of this course, the 22nd in our series, are also the third to be published by Springer-Verlag. Well over half of all stars seem to exist in binary systems. The study of binary evolution is therefore essential for our understanding of stellar evolution in general. The evolution of interacting binaries contains in itself many of the problems met in other fields of modern astrophysics. This is very apparent in these lecture notes.

Observational and Theoretical Issues of Interacting Binaries was the topic of the 22nd Advanced Course of the Swiss Society for Astrophysics and Astronomy. It was the first time that binary systems were the center of attention of our course. The established concept and organisation of the Advanced Course has been retained: three scientists, all acknowledged experts in their respective fields, were each invited to give nine one-hour lectures within the period of a week. The Advanced Course took place from April 6 to 11, 1992, at Les Diablerets, a charming resort in the Swiss alps. The high level of the lectures, the international background of the 65 participants, including many young students, and the beauty of the surroundings all contributed to the success of the course. The lecture notes of this course, the 22nd in our series, are also the third to be published by Springer-Verlag. Well over half of all stars seem to exist in binary systems. The study of binary evolution is therefore essential for our understanding of stellar evolution in general. The evolution of interacting binaries contains in itself many of the problems met in other fields of modern astrophysics. This is very apparent in these lecture notes.

The observational evidence for the existence of black holes has grown significantly over recent decades. Stellar-mass black holes are detected as X-ray sources in binary systems, while supermassive black holes, with masses more than a million times the mass of the Sun, lurk in the nuclei of galaxies. These proceedings provide a useful and up-to-date overview of the observations of black holes in binaries, in the center of the Milky Way, and in the nuclei of galaxies, presented by leading expert astronomers. Special attention is given to the formation (including the recent evidence from gamma-ray bursts), physical properties, and demographics of black holes.

The motivation for the workshop on which this book is based was the discovery in recent years of a large number of binary and millisecond radio pulsars, in the galactic disk as well as in globular star clusters, the oldest stellar systems in our galaxy. These discoveries have revolutionized our thinking on many aspects concerning the interior structure and evolution of neutron stars, and have revived the interest in the study of neutron star physics in general. In this book some three dozen of the world's experts in the field of radio pulsars, X-ray binaries, stellar evolution, neutron star interiors and stellar dynamics review the latest observational discoveries as well as the current theoretical thinking on the formation and physics of binary X-ray sources and of the binary and milli-second pulsars. These include discoveries such as that of the elevent millisecond pulsars in the globular cluster 47 Tucanae, the relativistic effects in the new double neturon star system PSR 1534+12 and spectacular results from Germany's ROSAT X-Ray Observatory.