Improvedly photostable, topically applicable cosmetic/dermatological sunscreen compositions well suited for enhanced photoprotection of human skin and/or hair against the damaging effects of UV-A and UV-B irradiation, particularly solar radiation, comprise (i) 4-tert-butyl-4′-methoxydibenzoylmethane, (ii) at least one particular 1,3,5-triazine compound, and (iii) at least one alkyl &agr;-cyano-&bgr;,&bgr;′-diphenylacrylate, formulated in a cosmetically/dermatologically acceptable vehicle, diluent or carrier therefor.