The combination of HPLC with phase-modulation spectrofluorometry provides fluorescence spectral and lifetime selectivity for the qualitative and quantitative analysis of Chromatographic peak components. The phase-modulation spectrofluorometer can be used for on-line HPLC detection and for batch analysis of Chromatographic fractions, as discussed in this paper for the analysis of mixtures of polycyclic aromatic hydrocarbons. In the case of on-line detection, fluorescence lifetime heterogeneity of Chromatographic peaks and peak portions is used as an indicator of Chromatographic peak purity. Fluorescence lifetimes and fractional intensity contributions can be determined from the observed phase and modulation lifetimes at an appropriate number of excitation modulation frequencies. Batch analysis of Chromatographic fractions can be performed by phase-resolved fluorescence spectroscopy, and involves the use of multidimensional data formats in which phase-resolved fluorescence intensity is plotted as a function of Chromatographic and fluorimetric experimental parameters. Advantages of the combined HPLC/phase-modulation spectrofluorometer system are discussed.