ObjectiveTo describe a real-time, continuous physiologic data acquisition system for the study of disease dynamics in the intensive care unit.DesignDescriptive report.SettingA 16-bed pediatric intensive care unit in a tertiary care children’s hospital.PatientsA total of 170 critically ill or injured pediatric patients.InterventionsNone.Main Outcome MeasuresNone.ResultsWe describe a computerized data acquisition and analysis system for the study of critical illness and injury from the perspective of complex dynamic systems. Both parametric (1 Hz) and waveform (125–500 Hz) signals are recorded and analyzed. Waveform data include electrocardiogram, respiration, systemic arterial pressure (invasive and noninvasive), central venous pressure, pulmonary arterial pressure, left and right atrial pressures, intracranial pressure, body temperature, and oxygen saturation. Details of the system components are explained and examples are given from the resultant physiologic database of signal processing algorithms and signal analyses using linear and nonlinear metrics.ConclusionsWe have successfully developed a real-time, continuous physiologic data acquisition system that can capture, store, and archive data from pediatric intensive care unit patients for subsequent time series analysis of dynamic changes in physiologic state. The physiologic signal database generated from this system is available for analysis of dynamic changes caused by critical illness and injury.