In an example, a composition for three-dimensional (3D) printing includes a polymer build material and a non-conductive fusing agent dispensable onto the polymer build material to form a polymer-fusing agent composite portion when heated to a sintering temperature, a conductive agent dispensable onto on the polymer build material to form a polymer-conductive agent composite portion when heated at least to the sintering temperature, the conductive agent comprising: at least one conductive particulate present in an amount of from about 10% to about 60% of a total weight of the conductive agent; at least one co-solvent present in an amount of from about 10% to about 50% of a total weight of the conductive agent; and an additive present in an amount of from about 0% to about 10% of a total weight of the conductive agent.