The authors review the role of bronchoalveolar and bronchial lavage in chronic obstructive lung disease patients. Only a few papers were published in the last ten years on this matter. In addition, data are incomplete and often conflicting, mainly because of the limited number of patients sampled and of non-standardized techniques of analysis. However, both bronchoalveolar and bronchial lavage are likely to be useful research tools to understand the pathophysiologic mechanisms underlying chronic obstructive lung disease.