Chemists have recognized the need for an instrumental technique that would yield complementary information to mass spectrometry in the analysis of complex mixtures. The development and application of gas chromatography/Fourier transform infrared spectrometry (GC/FTIR) is reviewed with emphasis on the factors affecting the performance of the capillary GC/FTIR interface. The present state of the art, particularly as it relates to the analysis of samples extracted from water and other environmental media, is described. The discussion covers chromatographic and optical considerations, chromatogram reconstruction, spectrum computation, and spectral searching. Achievement of the first subnanogram GC/FTIR spectrum is expected to occur in 1983 or 1984.