The current global dynamics have significant consequences on policy-making in and beyond the Arctic. To limit the effects of the ever more visible global climate crisis, however, multi-dimensional and multi-sided cooperation remain crucial. To better understand how legitimacies are constructed and used to intensify and to abandon different forms of cooperation and themes in policy-making (particularly at the local level) the proposed roundtable explored how different forms of legitimacy interact with different forms of Arctic cooperation. In the context of sustainable development, research on the Arctic illustrated how legitimacy is established by developing norms that are shared by many and through cooperation and how particularly the consideration of specific knowledges and of specific interpretations are used by actors to present their interests and approaches as legitimate. By considering also the “emotional turn” in social sciences and humanities, this roundtable discussed theoretical analyses, methodological perspectives and case studies on the nexus of emotions and legitimacy in Arctic cooperation, on different forms of legitimacy in cooperation (particularly since February 2022), their contestation and effects on policy-making in the Arctic at different governance levels.