Pneumoconioses are still a frequent cause of interstitial lung disease, that can be lethal. Nevertheless, the improvement of working conditions has led to a lower incidence of severe forms of disease. More sensitive diagnostic techniques, such as high resolution computed tomography scan, are used in early diagnosis and in the medico-legal expertise. Immunological techniques and mineralogical analyses of biological samples allow a more rigorous work-up in these cases. In this regard, bronchoalveolar lavage can bring very interesting information from the cellular, immunological, and mineralogical points of view.