This pilot study moves from the assumption that leadership is a relationship (and not a personality trait) and, therefore, that emotional intelligence is an essential quality for an effective leadership. This project moves also from the assumption that those who are able to negotiate show higher emotional intelligence and higher potential for leadership. Afterall, real leaders always negotiate. To test it, we involved Luiss University students who were enrolled both in the Laboratory of Negotiation (NegotiatingLab) and the New Technologies and Labour Law course: given its focus on negotiation, the former was considered the experimental group, while the latter was the control group. The results of this study show that studying the science of negotiation enables people to develop all the basic elements of emotional intelligence and, therefore, the leadership potential. In other words, we found that studying the science of negotiation – i.e. the science that enables us to learn about the emotions and interests of others (and, in turn, ours’) – is fundamental to developing emotional intelligence and leadership skills. More specifically, the findings show that, after attending the NegotiatingLab, students’ emotional intelligence increased of 8.62% on average vs. an increase of 0.60% registered among the students participating in the control group. Further, an improvement within the experimental group’s participants has been noted not only in terms of social awareness and relationship management (i.e. emotional intelligence’s inter-personal skills), but also in terms of self-awareness and self-management (i.e. emotional intelligence’s intra-personal skills). Moreover, we noted that at the end of the Negotiating Lab an increase in the four basic elements of emotional intelligence led to an enhancement of leadership potential. On the contrary, at the end of the New Technologies and Labour Law course the correlations among the examined variables remained unchanged, demonstrating no substantial modification in the relationship between emotional intelligence and leadership skills. This evidence imply that the science of negotiation should be recognized as a core competence for the future because it provides a mental training that enables people to develop four basic emotional intelligence skills (self-awareness, self-management, social awareness and relationship management) and, therefore, improves the quality of leadership. In other words, this study shows that emotional intelligence and leadership potential can be improved through the mental training provided by studying the science of negotiation. In this regard, scholars argue that the more emotionally intelligent individuals are more effective negotiators. This research shows that the relationship is also inverse: those who study the science of negotiation become more emotionally intelligent and increase their leadership potential. Given the above, we can say that people who have been studying negotiation are more emotional intelligent individuals and, as a consequence, they show a higher potential to be effective leaders. After all, if we carefully think about it, a negotiator must lead not only those on the same side of the table, but also those on the other side. A negotiator leads. A leader negotiates. Always. That’s why, moving from the idea that human life is an endless negotiation, the studying of the science of negotiation should be integrated into our school and university education systems. It will likely contribute to develop the leadership potential for the future.