Polydiorganosiloxane polyoxamide, linear, block copolymers and methods of making the copolymers are provided. The method of making the copolymers involves reacting a diamine with a precursor having at least one polydiorganosiloxane segment and at least two oxalyamino groups. The polydiorganosiloxane polyoxamide block copolymers are of the (AB).sub.n type.