A new descriptor of molecular structure for use in the derivation of predictive QSAR and QSPR models. EEVA, is described. EEVA (Electronic Eigen Value) is a modification of the recently proposed EVA approach, but it is based on computationally derived molecular orbital energies instead of vibrational frequencies. Like EVA, it is also invariant to alignment of the structures concerned. EEVAs performance has been tested in different applications and its predictive ability was clearly demonstrated. In particular, it seems to be suitable for ‘pure’ electronic substituent effectsi.e., for cases in which both hydrophobic and steric factors are of minor importance.