The technique of synchronous excitation is used to enhance the selectivity of luminescence spectrometry. The applicability of this simple methodology to the monitoring of trace organic pollutants such as the polynuclear aromatic compounds (PNA) originating from coal conversion processes is emphasized. Two specific examples are presented: the characterization of naphthalene derivatives in Synthane gasifier wastewater by synchronous fluorimetry, and multicomponent analysis of several PNA by synchronous room-temperature phosphorescence. © 1978, American Chemical Society. All rights reserved.