This book covers several areas, such as immunology, infectious diseases, physiology, general nursing, and medicine as well as measurement accuracy and the history of our understanding of fever. This book employs an interdisciplinary approach to exploring our concept of body temperature and specifically fever. The present volume revolves around thermometry, taking the reader on a journey from the past to the present. Yet while the emphasis is on the clinical importance of obtaining accurate, quantitative measurements of body temperature, the reader is also introduced to the most recent clinical work on the subject. This book represents a truly cross-disciplinary collaboration, using evidence-based practice to integrate physiological and immunological knowledge. The authors’ intention with this volume is to help readers gain better insight into the importance of using knowledge from different disciplines to develop an appreciation of the different aspects of body temperature. In addition, the reader will come to understand the concept of fever in a broader perspective than is traditionally adopted.