Recent investigations of the fundamental mechanisms of the mineral dust diseases have substantially increased our understanding of the pathogenesis of the pneumoconioses. In all the mineral dust pneumoconioses, the initial early lung lesion is a fibrosing macrophagic alveolitis. The additional contribution of other lung cell populations is currently under investigation and may identify specific processes for each of the pneumoconioses. Clinical investigations have also progressed with new tools such as Gallium-67 lung scanning, bronchoalveolar lavage analyses, and CT scanning of the thorax; their established values are reviewed in this paper, and areas where progress is needed are considered. The clinical progress in the mineral dust diseases is clearly linked to the basic understanding of the mechanisms of these diseases.