SIMON (Signal Interpretation and MONitoring) continuously collects and processes bedside medical device data. As of December 2009, SIMON has monitored over 7,630 trauma intensive care unit (TICU) patients, representing approximately 731,000 hours of continuous monitoring, and is currently operational on all TICU beds at Vanderbilt University Medical Center. Parameters captured include heart rate, blood pressures, oxygen saturations, cardiac function variables, intracranial and cerebral perfusion pressures, and EKG waveforms. This repository supports research to identify “new vital signs” based on features of patient physiology observable through dense data capture and analysis, with the goal of improving predictions of patient status. SIMON's alerting and reporting capabilities include web display, sentinel event notification, and daily summary reports of traditional and new vital sign statistics. This allows discoveries to be rapidly tested and implemented in a working clinical environment. The work details SIMON's technology and corresponding design requirements to realize the value of dense physiologic data in critical care.