The global and local electrophilicity indexes have been used to characterize the reactivity pattern of the C=C double bond towards nucleophilic addition reactions. A wide family of molecules including ketones, esters, anhydrides, nitriles and nitrocompounds containing appropriate substitution on the C=C double bond have been classified within an unique scale of reactivity. The predictive capability of the theoretical model is tested against a series of benzylidenemalononitriles and substituted alpha-nitrostilbenes.