In an example of a method for three-dimensional (3D) printing, a build material composition is applied to form a build material layer. The build material composition includes a polymeric or polymeric composite build material, and a precipitating agent. Based on a 3D object model, a fusing agent is selectively applied on at least a portion of the build material composition. The fusing agent includes a radiation absorber, which the precipitating agent precipitates. The build material composition is exposed to radiation to fuse the at least the portion to form a layer of a 3D part.