The method of localised 1H MR spectroscopy was used in 19 examinations in 9 patients with primary bone tumours in order to obtain spectral signals and to determine whether these are specific for tumour classification. The spectra were obtained by a double spin echo method and the tumour tissue showed very high water content and only minor lipid and proton signals which showed J-coupling characteristics. The latter are not found in normal bone marrow and are probably due to products of tumour metabolism. The resolution of the spectra within a 13 mm or 20 mm tissue cube depends largely on the structural homogeneity of the tumour. The signal patterns in the spectra were not specific to histological tumour types.