A method for adding color to a part during three-dimensional printing, the method comprising: selectively applying a core fusing agent (18, 28) on at least a portion of a build material (16, 102); exposing the build material to electromagnetic radiation, thereby fusing the portion of the build material in contact with the core fusing agent (18, 28) to form a core layer (46, 104); applying a layer of the build material on the core layer; applying a primer fusing agent (26, 26') on at least a portion of the build material layer; and exposing the build material layer to electromagnetic radiation, thereby fusing the portion of the build material layer in contact with the primer fusing agent to form a layer; wherein the method is characterized in that the primer fusing agent (26, 26') includes: cesium tungsten oxide nanoparticles; a zwitterionic stabilizer, wherein the zwitterionic stabilizer is selected from the group consisting of a C2 to C8 betaine, a C2 to C8 aminocarboxylic acid having a solubility of at least 10 g in 100 g of water, taurine, and combinations thereof; and an aqueous vehicle, wherein the aqueous vehicle includes water, a co-solvent, and a surfactant; and wherein the method further comprises: applying an other layer of the build material on the layer; applying a colored inkjet ink and i) the core fusing agent (18, 28) or ii) the primer fusing agent (26, 26') on at least a portion of the other build material layer; and exposing the other build material layer to electromagnetic radiation, thereby fusing the portion of the other build material layer in contact with the i) the core fusing agent (18, 28) or ii) the primer fusing agent (26, 26') to form a colored layer having a colorant of the inkjet ink embedded therein. selectively applying a core fusing agent (18, 28) on at least a portion of a build material (16, 102); exposing the build material to electromagnetic radiation, thereby fusing the portion of the build material in contact with the core fusing agent (18, 28) to form a core layer (46, 104); applying a layer of the build material on the core layer; applying a primer fusing agent (26, 26') on at least a portion of the build material layer; and exposing the build material layer to electromagnetic radiation, thereby fusing the portion of the build material layer in contact with the primer fusing agent to form a layer; wherein the method is characterized in that the primer fusing agent (26, 26') includes: cesium tungsten oxide nanoparticles; a zwitterionic stabilizer, wherein the zwitterionic stabilizer is selected from the group consisting of a C2 to C8 betaine, a C2 to C8 aminocarboxylic acid having a solubility of at least 10 g in 100 g of water, taurine, and combinations thereof; and an aqueous vehicle, wherein the aqueous vehicle includes water, a co-solvent, and a surfactant; and applying an other layer of the build material on the layer; applying a colored inkjet ink and i) the core fusing agent (18, 28) or ii) the primer fusing agent (26, 26') on at least a portion of the other build material layer; and exposing the other build material layer to electromagnetic radiation, thereby fusing the portion of the other build material layer in contact with the i) the core fusing agent (18, 28) or ii) the primer fusing agent (26, 26') to form a colored layer having a colorant of the inkjet ink embedded therein.