The aminoacetophenones belong to the class of highly-polar molecules denoted D--A, where D is an electron donor substituent, is a disubstituted benzene ring and A is an electron acceptor substituent. Of the various {o, m, p} isomeric triads of the D--A type which have been investigated (i.e., nitroanilines2, fluorobenzonitriles3, cyanoanisoles4, and cyanoanilines5), the aminoacetophenones are the most polar subset for which all three isomeric members exhibit both fluorescence and phosphorescence. In the most polar subset, the nitroanilines2, theo-andm-isomers fluoresce only whereas thep-isomer phosphoresces only. In the less polar subsets, all isomers exhibit both fluorescence and phosphorescence. Hence, the aminoacetophenones are of interest in determining whether or not the peculiar luminescence characteristics of the nitro-aniline subset are a generic effect of increased molecular dipolarity or are merely the result of a fortuitous arrangement of the excited electronic states introduced by the nitro group.