State-specific multireference M ller-Plesset perturbation theory has been applied to the study of valence and Rydberg excitation energies of benzene. The results compare well with experiment. The calculated valence π-π * excitation energies (experimental values in parentheses) are 1 B 2 u , 4.77 (4.90), 1 B 1 u , 6.28 (6.20), 1 E 1 u , 6.98 (6.94) and 1 E 2 g , 7.88 (7.80) eV. Results of similar accuracy are obtained for the valence triplet excited states. The Rydberg excitation energies are also predicted with an accuracy of 0.18 eV or better.