Camille Toussaint, Associate Researcher at i3-CRG, has been awarded the AIMS thesis prize for her work in management science entitled "Gérer en commun un problème complexe d'échelle planétaire? Le cas des débris spatiaux", defended in December 2022 under the supervision of Hervé Dumez.

Complex problems on a planetary scale present a challenge for the organization of collective action, given their complexity, multidimensionality and the heterogeneity of their stakeholders. What are the management methods used by the actors involved to deal with this type of empirical situation? This thesis focuses on the case of space debris, the proliferation of which in Earth orbits threatens the continuation of space activities. The problem can be considered from the angle of regulation, the market or the commons.  Successive analysis of these three management modes reveals several sets of results. Firstly, a polycentric system is set up, organized around several coordinated regulatory centers. Secondly, the proliferation of space debris has given rise to a new market of collective interest, leading to the emergence of different player strategies and a dynamic interplay between several market categories. Thirdly, the community of experts, known as "global gossipers" because of their affective relationship with the problem, plays a central role in the production and dissemination of knowledge. Taken together, these results allow us to identify "global commoning" as a new way of managing complex problems on a planetary scale.  The thesis enriches the theory of the commons by clarifying the modes of coordination of polycentrism, and by transposing the notion of commoning to the global scale. It contributes to research on grand challenges by emphasizing the importance of the affective dimension of the individuals involved.