This paper deals with indirect Raman difference spectroscopy, a mode of difference spectroscopy adapted to multi-channel spectrometers, in which the Raman spectra to be compared are recorded successively, the calibration of the spectrometer for successive recordings being linked by means of a reference spectrum. The overall experimental procedure is described and discussed. The results of some measurements of Raman wavenumber shifts due to solvent, ionic and isotopic effects are given. The upper limit of the error seems to be 10-2 cm-1. The method can be applied to various types of samples, including solids. © 1998 John Wiley & Sons, Ltd.