This is a prospective longitudinal study of adult patients with chronic obstructive pulmonary disease (COPD) who will be enrolled when their COPD is considered clinically stable or during an acute exacerbation. This design will allow both within-person and between-person comparisons by exacerbation experience. Comprehensive clinical and patient-reported assessments will be performed at baseline and at 3 months (end of study). Subsets of items will be administered by interactive voice response (IVR) over the course of the study to measure changes in key symptoms over the course of recovery from an exacerbation. A subset of patients will be interviewed at the end of the study to assess content validity of PROMIS items in this patient population.