Applications of some selected elemental determinations of different catalytic materials by radioisotope excited x-ray fluorescence will be presented. The analytical method, an improved sample preparation and analysis technique were presented at the last Denver Conference (1). Data on the accuracy and precision of each of the following types of catalysts are presented. 1) Platinum catalysts (0.5 - 10% Pt) on alumina and carbon supports used for dehydrogenation, hydrohalogenation, oxidation processes, etc. 2) Palladium catalysts (0.5% - 10% Pt) on alumina and carbon supports employed for alkylation, decarbonisation, hydrogenation, etc.