The key to the successful management of many chronic diseases is avoiding acute episodes. Managing chronic illness such as heart failure accounts for roughly 75% of health care costs in the United States. In this Distinguished Lecture, John Guttag of MIT discusses two software-intensive projects aimed at dramatically reducing the time between a physiological change in the patient and a therapeutic intervention. Guttag first describes a novel approach to the prompt detection of epileptic seizures from scalp EEG. He concludes by describing a preliminary version of a software tool designed to help physicians deal with the nearly overwhelming amounts of physiological data that is becoming available. From the Series:CSE Colloquia - 2006