Abstract The “interfacial polymerization” method was utilized for the preparation of organotin esters. Trialkyl-or triaryl-tin chlorides, dialkyltin dichlorides and tetraalkydichlorodistannoxanes, dissolved in an inert solvent, were reacted with an aqueous solution of an alkali metal salt of a mono-or dicar☐ ylic acid, to yield the organotin esters in high yield.