This paper explores the use of Design Thinking (DT) as a vehicle to improve negotiation results, by preparing the negotiation using an ideation to explore the different potential options which facilitate the arrival to a deal. Since Design Thinking is accepted as an analytical and creative process to experiment and create models, gather feedback and adjust results, our research has experimented this cycle of activities during the preparation for a complex negotiation between one government customer and a private company, over the creation of a public private partnership (PPP) contract. The exercise was a simulation with university students through a role-play, comparing results between those teams who prepared their negotiation using Design Thinking versus those—from the control group—, who prepared the negotiation with conventional tools without exercising DT. The results as well as the emotions experimented by the participants showed the benefits of using DT to prepare for the negotiation. The author’s goal is to identify the benefits of using DT as a negotiation tool, which can provide more elaborated agreement options, as well as to improve the negotiation climate among the parties. The final goal of the article is to increase the understanding of DT as a tool to stimulate creativity, generate a better climate, and contribute to the creation of mutually beneficial options in a better climate for the negotiation.