Hospital patients can experience serious adverse events during their stay. To identify, review and treat these patients and to prevent serious adverse events, we introduced a medical emergency team (MET) service into our hospital in September 2000 following a 1-year period of preparation and education. The introduction of the MET into our institution has been associated with profound changes to cultural and medical practice that have affected the way in which the intensive care unit and the hospital view the roles of junior doctors, nurses, intensive care physicians, and senior doctors. These changes have also been associated with a progressive reduction in the incidence of cardiac arrests of close to 70%. Furthermore, they have allowed improved analysis and characterization of 'at-risk' patients and their needs. Four years later, we remain glad we MET.