Phenylethyl resorcinol (4-(1-Phenylethyl) 1,3-benzenediol) also known as SymWhite 377, a hydroxy‐stilbene derivative, is a potent, stable and safe skin lightener. It exerts tyrosinase and melanin synthesis inhibitory activity. Anti-melanogenic activity of phenylethyl resorcinol is mediated by activation of p44/42 MAPK. The Chinese State Food and Drug Administration (SFDA) has approved SymWhite 377, a skin brightening active from supplier Symrise, as an ingredient for cosmetic applications.