The publication of proceedings of conferences has often been so delayed that they are useless both to active workers in the field and for cur- rently appropriate teaching. Rapid publication on the other hand may impose very difficult conditions upon authors and demand unwelcome sacrifices. We wish to thank the many speakers at ESCAT for their co- operation in providing manuscripts and to apologise to those unable for reasons beyond their control to fall in with the rigorous editorial policy. To get this book out at the earliest possible moment we have also cut the normal consultation between...