Why write a book on emergency radiology? In many countries, hospital emergency departments have become a major part of the healthcare safety net. In the last decade economically-driven structural changes in health care delivery have caused a dramatic increase in emergency department visits. In response to capacity and staffing pressures, hospitals are developing and implementing a variety of strategies designed to improve patient flow and reduce overcrowding in the emergency department. Several factors are considered critical for success, such as having the right multidisciplinary teams in place and optimizing the use of imaging tests. For a critical care physician it is paramount to obtain the images quickly and for them to be interpreted accurately. To accomplish this, the emergency radiology division should be located adjacent to or within the emergency department. High quality emergency radiology services combine state-of-the art equipment and unsurpassable expertise available 24 hours a day. The demands for radiologists with specific knowledge in diagnostic and interventional emergency radiology is continuously increasing. The emergency radiology services should be equipped with sophisticated imaging (especially Multidetector Computed Tomography, MDCT) and information technologies (Picture Archiving and Communication System, PACS). The rapid development of MDCT technology has dramatically changed CT applications. In many imaging centers the volume of MDCT scans is growing at least 10% annually while the number of radiographic studies decline. There is an increasing trend towards the use of MDCT to evaluate traumatic injuries and non-traumatic emergencies. The use of workstations for reporting and for further image reconstruction becomes standard practice. On the occasion of the European Congress of Radiology (ECR) 2003 and 2004 a Categorical Course on "Emergency Radiology" has been organized to assess current developments and concepts in this rapidly growing field. Numerous radiologists, all outstanding and internationally renowned experts in their field, have made superb contributions in an ECR syllabus. These authors have now made a second effort and updated their contributions for this book. The chapters in the book mirror the topics presented in the ECR course, encompassing imaging approaches as well as interventional aspects. A separate section is devoted to pediatric emergencies. We would like to express our thanks and appreciation to all contributers for their excellent written material. This comprehensive work would not have been accomplished without their enthusiasm. We hope this book will be a "Go-To" reference to general radiologists who have to deal with traumatic and nontraumatic emergencies. Similarly, it should serve as reference for emergency medicine physicians. Finally, radiology residents should find this book useful when covering the emergency department.