On the occasion of the retirement of Ulrich Schwarz, a symposium was held in Groningen in May of 1996, celebrating his contributions to the study of the int- stellar medium, including his work on the high-velocity clouds. The coming together of many specialists in the latter ?eld prompted the idea of compiling a book c- taining their contributions, and summarizing the status of our understanding of the high-velocity cloud phenomenon. This seemed especially worthwhile at the time, since many exciting developments were taking place. After the discovery of some H i clouds with high velocities, about 40 years ago, the subject had been dominated by 21-cm observations of H i emission. Starting in the mid-1980s much progress was being made because of the availability of new instruments, such as large ground-based optical telescopes and UV observatories in space. The connections between the work on high-velocity clouds and other studies of the properties of the (hot) interstellar medium also became clearer.

This volume contains the proceedings of an international conference on Shocks in Astrophysics held at UMIST, Manchester, England from January 9-12, 1995. The study of interstellar and circumstellar gas dynamics has a long and distinguished history in Manchester and has been almost entirely concentrated in the school founded by Franz Kahn in the Astronomy Department, University of Manchester. In January 1993, one of us (AR) was appointed to the faculty of the Astrophysics Group in the Department of Mathematics at UMIST and astrophysical gas dynam ics became a major interest of the Group. The subject of this conference was chosen partly for the topicality of the subject matter and partly to help synthesise this expertise with the expertise in interstellar chemistry already present in the Group. The first fruits of this synthesis are contained in this volume. As it happened, this conference celebrated, not so much the beginnings of a long and fruitful collabo ration, but rather gave many of Alex's friends the chance to say a fond farewell as he departed UMIST at the end of January 1995 to take up a chair at UNAM, Mexico City. The core of this volume consists of twelve review articles, marked (R) in the list of contents, incorporating observational and theoretical studies of shock waves in a variety of situations from Herbig-Haro objects to Supernova Remnants to Active Galactic Nuclei. We have also included the contributed (C) and poster (P) papers.

Proceedings of the international workshop on the 'Evolution of Interstellar Matter and Dynamics of Galaxies'.

From the reviews: Astronomy and Astrophysics Abstracts has appeared in semi-annual volumes since 1969 and it has already become one of the fundamental publications in the fields of astronomy, astrophysics and neighbouring sciences. It is the most important English-language abstracting journal in the mentioned branches. ... The abstracts are classified under more than hundred subject categories, thus permitting a quick survey of the whole extended material. The AAA is a valuable and important publication for all students and scientists working in the fields of astronomy and related sciences. As such it represents a necessary ingredient of any astronomical library all over the world." Space Science Reviews #1 "Dividing the whole field plus related subjects into 108 categories, each work is numbered and most are accompanied by brief abstracts. Fairly comprehensive cross-referencing links relevant papers to more than one category, and exhaustive author and subject indices are to be found at the back, making the catalogues easy to use. The series appears to be so complete in its coverage and always less than a year out of date that I shall certainly have to make a little more space on those shelves for future volumes." The Observatory Magazine #1