Acrylonitrile-styrene-glycidyl methacrylate (N/S/G) terpolymers were prepared by bulk polymerization by using benzoyl peroxide as initiator and analyzed by NMR spectroscopy. The compositions of terpolymers were determined by quantitative C-13{H-1}-NMR spectra and compared with those calculated by Goldfinger's equation by using comonomer reactivity ratios: r(NS) = 0.04, r(SN) = 0.40; r(NG) = 0.22, r(GN) = 1.37; r(SG) = 0.44, r(GS) = 0.53. The C-13{H-1}- and H-1-NMR spectra were overlapping and complex. The spectral assignments were done with the help of distortionless enhancement by polarization transfer and two-dimensional C-13-H-1 heteronuclear single quantum correlation experiments. 2D total correlated spectroscopy was used to ascertain the various coupling between the protons. The methyl, methine, methylene, and oxymethylene carbon resonances showed compositional sensitivity. 2D nuclear Overhauser enhancement spectroscopy (NOESY) experiment was used to ascertain the spatial proton-proton couplings. (C) 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 1779-1790, 2003.