IntroductionClimate change presents a growing threat to global mental health, disproportionately affecting Indigenous Peoples. Globally, Indigenous communities face unique and compounded climate change-related burdens, intensified by histories of colonization and structural oppression. The Wellcome-funded Connecting Climate Minds (CCM) initiative was established to cultivate a collaborative, transdisciplinary field and research and action agenda dedicated to addressing the complex interplay between climate change and mental health, and included a dedicated focus on Indigenous communities.MethodologyBetween March 2023 and May 2024, CCM convened a diverse group of experts across disciplines, sectors, and countries. This included two online and one in person dialogues and collaboration with representatives from Indigenous groups, guided by an Indigenous Advisory Group. One online dialogue had global representation, and one convened members of the Kom community in Cameroon and Nigeria, and the Anam tribal community in Kenya. The in person inter-community dialogue convened Kichwa communities in the Northern Peruvian Amazon. The dialogue insights were used to develop a global research and action agenda focused on understanding and addressing the mental health needs of Indigenous Peoples experiencing the climate crisis. The process prioritized adapting informed consent protocols to align with Indigenous sovereignty, ensuring access for non-English speaking participants, and centering Indigenous framings of mental health and climate change, such as ecological wellbeing and kinship relationships.ResultsThe resulting research and action agenda for Indigenous mental health in a changing climate highlights critical challenges. These include the detrimental impacts on Indigenous mental health and wellbeing of extractivism, struggles for land rights, lack of territorial sovereignty, and the resulting disconnection from land, food insecurity, and forced displacement that are created and exacerbated by climate change. These issues amplify existing intergenerational trauma and contribute to a profound loss of cultural identity. The agenda identifies key research priorities: understanding climate-related disruptions to traditional practices and spiritual connections, exploring how colonial violence and climate crises interact and intensify mental health impacts, integrating ancestral and traditional medicinal approaches to caring for people and nature in the climate crisis, and understanding the impact of territorial sovereignty on mental health.ConclusionThis agenda underscores the imperative for researchers, policymakers, and practitioners to adopt frames aligned with Indigenous worldviews. Implementing research, policies, and programs that acknowledge and support cultural practices and dynamic transmission—a two-way communication between Indigenous worldviews and Western biomedicine—is crucial. This approach not only promotes mental health but also contributes to the overall wellbeing of both people and the planet. The process lessons learned, particularly around enabling collaborations, respecting Indigenous sovereignty, and ownership of knowledge, are vital for future research in this area, fostering right relations and ensuring that diverse ways of knowing and doing are integrated into wider climate and mental health action.