Chronic obstructive pulmonary disease (COPD) is a prevalent and disabling chronic disease which incurs a high cost to health care system. Even with optimal treatment, people with COPD have high rates of hospital admission due to exacerbations of their disease. Currently, care provided to people with COPD is predominantly reactive and episodic. A better approach is needed. This project leverages mobile and wearable technology to detect when patients are deteriorating to enable proactive early interventions that prevent hospital admissions.