Enormous advances in information technology have permeated essentially all facets of life in the past two decades. Formidable challenges remain in fostering tools that enhance productivity but are sensitive to work practices. Cognitive Informatics (CI) is the multidisciplinary study of cognition, information and computational sciences that investigates all facets of human computing including design and computer-mediated intelligent action, thus is strongly grounded in methods and theories from cognitive science. As an applied discipline, it has a close affiliation with human factors and human-computer interaction, and provides a framework for the analysis and modeling of complex human performance in technology-mediated settings and contributes to the design and development of better information systems. In recent years, CI has emerged as a distinct area with special relevance to biomedicine and health care. In addition, it has become a foundation for education and training of health informaticians, the Office of the National Coordinator for Health Information Technology initiating a program including CI as one of its critical elements to support health IT curriculum development. This book represents a first textbook on cognitive informatics and will focus on key examples drawn from the application of methods and theories from CI to challenges pertaining to the practice of critical-care medicine (CCM). Technology is transforming critical care workflows and re-organizing patient care management processes. CCM has proven to be a fertile test bed for theories and methods of cognitive informatics. CI, in turn, has contributed much to our understanding of the factors that result in complexity and patient errors. The topic is strongly interdisciplinary and will be important for individuals from a range of academic and professional backgrounds, including critical care specialists, psychologists, computer scientists, medical informaticians, and anthropologists.