Intensive Care Medicine. The first four editions have established this text as a leading source of information in the rapidly changing and complex field of critical care. The editorial challenge for the fifth edition was to ensure that the textbook continued to evolve, improve, and change to meet the rigorous demands placed on it by clinicians in all specialties practicing in the adult intensive care environment without losing the fundamental strengths that have made it so useful and popular. A particular challenge was to update the text and incorporate new material while judiciously discarding older information. We hope and believe that the fifth edition of Irwin and Rippe's Intensive Care Medicine has risen to the multiple challenges that we as editors have faced.