The advantages and limitations of x-ray fluorescence analysis in the study of museum objects are briefly discussed. The apparatus used for the non-destructive analysis of large objects at the Laboratoire de Recherche, at the Palas du Louvre is described and pictured. Also described is the application of small limiting apertures for micro-x-ray fluorescence analysis of small quantities and selected areas to the study of pigments in paintings, mosaics, ceramics and glazes, gems and minerals and corrosion products and inclusions in metals.