Fourier transform-infrared (FT-IR) and FT-Raman spectra have been recorded from poly (aryl ether sulphone) and poly (aryl ether sulphone), and some tentative assignments of the observed bands are presented. FT vibrational spectroscopy techniques have also been used to study a series of aryl ether sulphone/aryl ether ether sulphone copolymers. Relative intensities of bands in both the FT-Raman and FT-IR spectra may be associated with the ratio of the components in the copolymers.