Respiratory bronchiolitis associated with interstitial lung disease (RB-ILD), first described by Niewoehner et al in an autopsy study of cigarette smokers who died from non pulmonary causes in 1974, is a rare entity that should be distinguished from the other interstitial lung diseases and in particular from desquamative interstitial pneumonia, although the two conditions share a similar histopathological pattern. RB-ILD is clearly connected with tobacco smoking and has been inserted in the "smoking related interstitial lung diseases" together with DIP and Cell histiocytosis of Langerhans; it may also be associated with occupational exposure to machine fumes. The following is a case report of a patient with both smoking and occupational exposure.