An example of a fusing agent includes a metal bis(dithiolene) complex, a thiol surfactant, a polar aprotic solvent, and a balance of water. In an example of a method of making the fusing agent, the metal bis(dithiolene) complex is exposed to an aqueous solution including a reducing agent and a thiol surfactant to form a reduced metal bis(dithiolene) complex and to dissolve the reduced metal bis(dithiolene) complex in the aqueous solution. The aqueous solution is incorporated into a vehicle including a water soluble organic solvent and an additive selected from the group consisting of an emulsifier, a surface tension reduction agent, a wetting agent, a scale inhibitor, an anti-deceleration agent, a chelating agent, an antimicrobial agent, and a combination thereof. The fusing agent may be utilized in a three-dimensional printing method and/or incorporated into a three-dimensional printing system.