Observations with X-ray satellite ROSAT over the past 5 years have established supersoft X-ray sources as a new class of objects in our Galaxy and beyond. Optical follow-up observations have revealed the binary nature of several of them. Recent population synthesis calculations have shown that the number of such binaries is expected to be considerably larger than those of the common low- and high-mass X-ray binaries. This book provides the first comprehensive overview of the many recent observational discoveries and theoretical investigations. It describes relations between supersoft sources and other areas in astrophysics. This volume also comprises a complete catalog of presently known supersoft sources including a comprehensive bibliography of observational results.

The contributions to the 151st IAU Colloquium cover different fields of recent research, observational as well as theoretical, on solar and stellar flares ranging from radio up to gamma-ray wavelengths. A special chapter is devoted to all-sky monitoring and, finally, the excerpts of a round-table discussion present the reader with an interesting outlook on future developments. This book is therefore a unique source for those who want to get a complete picture of this fascinating part of modern astrophysics.

The Third Microquasar Workshop (or the 'Fifth' Workshop on Galactic Relativ istic Jet Sources), was held in Granada, Andalucia (Spain) on 11-13 September 2000. The aim of this workshop in Granada, following the previous Microquasar Workshops in Greenbelt (1997) and Paris (1998) and the Workshops on galactic sources with relativistic jets in Jodrell Bank (1996) and Milton Keynes (1998), was to focus on the theoretical and observational aspects of microquasars. The study of microquasars, the sources in our Galaxy displaying powerful re lativistic jets, is a rapidly advancing field in astrophysics. The new instrumentation on ground (MERLIN, SCUBA, VLA, VLT) and aboard satellites (ASCA, BSAX, ISO, IXAE and RXTE) has provided important results, and much more is expected to come from Chandra and XMM-Newton. In the further future, powerful instru mentation will come online in the sub-mm (ALMA) and gamma-rays (INTEG RAL), extending our coverage to important regions for the study of microquasars. Energy transport via relativistic jets is one of the most important physical mechan isms taking place in compact objects. Large efforts have been devoted to properly understand the disk-jet connection, and even the effects of rotation or magnetic fields. Several new important advances have been made recently, both from the point of view of the theoretical treatment of jets and the different new observational tests.

The Third Microquasar Workshop (or the 'Fifth' Workshop on Galactic Relativ istic Jet Sources), was held in Granada, Andalucia (Spain) on 11-13 September 2000. The aim of this workshop in Granada, following the previous Microquasar Workshops in Greenbelt (1997) and Paris (1998) and the Workshops on galactic sources with relativistic jets in Jodrell Bank (1996) and Milton Keynes (1998), was to focus on the theoretical and observational aspects of microquasars. The study of microquasars, the sources in our Galaxy displaying powerful re lativistic jets, is a rapidly advancing field in astrophysics. The new instrumentation on ground (MERLIN, SCUBA, VLA, VLT) and aboard satellites (ASCA, BSAX, ISO, IXAE and RXTE) has provided important results, and much more is expected to come from Chandra and XMM-Newton. In the further future, powerful instru mentation will come online in the sub-mm (ALMA) and gamma-rays (INTEG RAL), extending our coverage to important regions for the study of microquasars. Energy transport via relativistic jets is one of the most important physical mechan isms taking place in compact objects. Large efforts have been devoted to properly understand the disk-jet connection, and even the effects of rotation or magnetic fields. Several new important advances have been made recently, both from the point of view of the theoretical treatment of jets and the different new observational tests."