Acute exacerbations of chronic obstructive pulmonary disease (AECOPDs) frequently cause patients with COPD to access the emergency department and have a negative impact on the course of the disease. The objectives of our study were: 1) describing the socio-demographic and clinical characteristics, and the clinical management, of patients with AECOPD, when they present to the emergency department; and 2) estimating the costs related to the management of these patients. We conducted a retrospective cohort study in Italy, collecting data on 4396 patients, from 34 centres.