The present invention generally relates to an aqueous herbicidal formulation that comprises at least one phenoxy acid herbicide or an agriculturally acceptable salt or derivative thereof, and an alkylamidopropyl dialkylamine surfactant adjuvant, wherein said surfactant adjuvant comprises at least one surfactant having the formula (I) wherein R is a straight or branched chain, saturated or unsaturated acyl group having 6-22 carbon atoms, n is 3, and Y and Y are, independently, an alkyl group having 1-4 carbon atoms or (AO)