The Rio Climate Challenge 2015, two months before the Paris Conference, gathered a group of prestigious climate thinkers to get deeper into some ideas in the context of the Brazilian Climate Centre, our think tank that had just been registered officially. The meeting guided the action of Alfredo Sirkis and Everton Lucero, in the Brazilian Delegation, who managed to include the recognition of the economic value of mitigation actions (the positive pricing of the minus-carbon) in Paragraph 108. In the meeting Dipak Dasgupta, a Hindu economist from the Green Climate Fund, presented a rapporteurs’ paper of great importance.