Early Warning Systems (EWS) enable timely detection of clinical deterioration in hospitalized patients by systematically assessing vital signs. Tools like NEWS2, MEWS, and qSOFA help identify risk and trigger interventions, including activating Medical Emergency Teams (MET). Common causes of decline include infections, cardiovascular, respiratory, neurologic, or metabolic events. Regular monitoring - especially in high-risk or elderly patients - is essential. EWS improve patient safety and are increasingly part of quality measures, such as mandatory sepsis screening in Germany from 2026. Integration into digital records and staff training are key for effective implementation and outcome improvement.