The fusion of basic ideas in mathematics, radar, sonar, biology, and chemistry with ongoing improvements in hardware and computation offers the promise of much more sophisticated and accurate detection and identification capabilities than currently exist. Coupled with the dramatic rise in the need for surveillance in innumerable aspects of our daily lives, brought about by hostile acts deemed unimaginable only a few short years ago, the time is ripe for image processing scientists in these usually diverse fields to join together in a concerted effort to combat the new brands of terrorism. We envisage the proposed ASI as one important step. To encompass the diverse nature of the subject this volume covers three broadly defined but interrelated areas: I. The mathematics and computer science of automatic detection and identification; II. Image processing techniques for radar and sonar; III. Detection of anomalies in biomedical and chemical images. A deep understanding of these three topics, and of their interdependencies, is clearly crucial to countering the increasing sophistication of those who wish to do us harm. The contributors to this volume include many of the world's leading experts in the development of new imaging methodologies to detect, identify, and prevent or respond to these threats.