The use of x-ray diffraction methodology for the analysis of compounds of occupational health concern was reviewed. Compounds suited for x-ray diffraction analysis included boron-oxide (1303862), calcium-oxide (1305788), cobalt (7440484) fumes and dusts, copper (7440508) fumes and dusts, iron-oxide (1332372) fumes, magnesium-oxide (1309484) fumes, vanadium-oxide (1314347), zinc- oxide (1314132), quartz (14808607), cristobalite (14464461), asbestos (1332214), and talc (14807966). Sample preparation methods applicable to x-ray diffraction techniques included bulk sample collection, membrane filter samples from personal air samplers, large membrane filter samples from high volume air samplers, samples of settled dusts, and biological samples. The use of x-ray diffraction for qualitative and quantitative purposes was described. Qualitative identification was based on a variety of indexing systems that compared inorganic compounds and minerals to known standard powder diffraction patterns. Quantitative methods included direct comparison based on intensity measurements of known and unknown components and the internal standard method involving determination of the ratio of diffracted intensity of the unknown component in various mixtures with known components. Specific considerations for each type of analysis were included in the discussion.