The present invention relates to a composition comprisinga) an anionic compound having wetting and dispersing properties selected from the group ofa1) an alkyl naphthalene sulfonate,a2) a naphthalene sulfonate-formaldehyde condensate that may optionally be alkyl substituted and mixtures thereof, andb) a nitrogen-containing surfactant selected from the group consisting of alkylamine alkoxylates, alkylamidoamine alkoxylates, alkanolamides and their alkoxylates, alkylamidopropylamines, betaines, amino acids, or any mixtures thereof,wherein the molar amount of anionic sulfonate and, if any are present, carboxylate groups in the composition is in excess of the molar amount of nitrogen-containing groups. These compositions exhibit synergistic wetting properties as compared to the surface-active components taken alone. Further, the compositions also exhibit an increased rainfastness. The compositions can be used as a wetting agent and/or as an agent for increasing rainfastness in cleaning or agrocultural formulations. The invention also relates to an agrocultural formulation per se.