The fractionation and analysis scheme for the enrichment and subsequent determination of trace polynuclear aromatics is described. The method is generally applicable to a detailed analysis of any complex mixture containing polynuclears, but the example was chosen from the application to airborne particulate matter. After the extraction of polynuclear hydrocarbons and several partitioning steps, the sample was subjected to fractionation on a lipophilic gel. The collected fractions were further chromatographed by high-resolution LC on polar chemically bonded stationary phases. Fraction trapping was followed by capillary column GC, and non-destructive spectral methods such as UV, fluorescence emission, and NMR spectroscopy were also used to yield additional information.