Abstract: A process for the preparation of amino-substituted organopolysiloxanes which comprises the steps of mixing a catalyst comprising both (i) at least one compound selected from barium hydroxide and strontium hydroxide and (ii) at least one compound selected from borates and phosphates of sodium with (A) a silanol terminated organopolysiloxane compound and (B) an organosilicon compound having at least one silicon-bonded alkoxy or alkoxyalkoxy group and a monovalent substituent composed of carbon, nitrogen and hydrogen and having at least one --NH.sub.2 therein attached to silicon by way of a silicon to carbon linkage and thereafter allowing (A) and (B) to react at a temperature of at least 50.degree. C.