Respiratory bronchiolitis-associated interstitial lung disease (RB-ILD) is a disease that exclusively affects cigarette smokers. Long-term prognosis is good with cessation of smoking, in combination or not with corticosteroid therapy. We report here the case of a 50-year-old patient with RB-IL diagnosed on lung biopsy. Despite corticosteroid and cyclophosphamide therapy, no functional or radiological improvement was obtained. In contrast, cessation of smoking was associated with the disappearance of the infiltrative opacities. Clinical and radiological parameters remained stable during follow-up (13 years) while a moderate obstructive pattern appeared.