The possibilities and limitations of analyses of polychlorinated biphenyls (PCBPs) by capillary gas chromatography and capillary gas chromatography-mass spectrometry have been investigated. Metal capillary columns (WCOT) coated with Apiezon L and OV-101 were not suitable for PCB analyses. Good results were obtained in the separation of model mixtures of PCBs and of Aroclor 1242 on a glass capillary column coated with OV-101. Sources of error are indicated that may be encountered in the characterization of PCB components in Aroclor 1242 by standard additions, Kováts' retention indices and mass spectrometry. The direct coupling of a capillary column (WCOT) to a mass spectrometer produced spectra of the main PCB components, many of which could be used in the identification of isomeric PCBs.