Chronic obstructive pulmonary disease (COPD) is a highly prevalent disease that has a large impact on quality of life for patients and their families and kills millions of people worldwide. Even though there have been significant advances in the understanding and management of COPD, suggesting that the disease may be largely preventable, it remains only marginally treatable. This is probably because COPD is due to a slowly progressive destructive process of the lung that is poorly reversible when manifested clinically, and because it has systemic effects and frequent comorbidities that should be managed more comprehensively.The interest in COPD by the medical and scientific community has increased dramatically in the last decade, as reflected by the number of publications in both pulmonary and general medical journals. This review aims to summarize and highlight progress in the understanding of COPD in 2005. Although we found most of the articles interesting, we had to be selective, and we take full responsibility for the choices we have made.