SUMMARYBased on a statistical model of the reproducibility of NMR spectral features, a system for computer retrieval of high-resolution 'H-NMR spectra of glycoprotein carbohydrates has been developed. For corresponding peaks in an unknown and a reference spectrum, a similarity index based on the reproducibility of the chemical shifts is calculated. In addition, a second similarity index, based on the probability distribution of the percentage of non-matching peaks, has been developed. From these two similarity indices, a combined similarity index using the recall-reliability function as the optimizing criterion has been derived.First results indicate that the "H-NMR reproducibility-based retrieval' ('1HRR') system offers good perspectives for both identification and substructure analysis.