Founder of 1000mercis SA, Yseulys Costes currently occupies the position of Chairman & Co-Chief Executive Officer at 1000mercis SA and Chairman at Positive Ympact SAS.

She is also on the board of SEB SA and Ocito SA (former Chairman-Supervisory Board) and Member-Strategy Board at City of Paris and Member of Conseil pour la Diffusion de la Culture Économique.

In her past career Yseulys Costes occupied the position of Member of Conseil des Entreprises et Groupements de l'Economie Sociale.

She received a graduate degree and an undergraduate degree from Université Paris Dauphine-PSL, an undergraduate degree from Université Paris 1 Panthéon-Sorbonne and an MBA from Anderson School of Management.