Climate change is increasing temperature variability and extremes, causing both direct effects on health (e.g., death, heat stress) and indirect impacts on food and water supplies. Research by our team and others has clearly demonstrated that climate change disproportionately affects individuals and communities that experience social and environmental vulnerabilities and discrimination. There is a critical need for evidence- based solutions to reduce the impacts of the warming climate on marginalized communities to enable timely, effective, and impactful interventions. The Center for Climate: Equitable and Accessible Research-based Testing for Health (C-EARTH) will catalyze transdisciplinary research approaches involving individual- and policy-level solutions to address multiple climate risks to human health, particularly in populations at greatest risk, reflecting our environmental justice and health equity goals. The aims of C-EARTH are to: 1) create new research capacity for the development and evaluation of climate change and health (CCH) solutions to address the consequences of heat and improve health equity, catalyze collaborations across disciplines, support career development of early-stage investigators, oversee a community-based pilot grant program on CCH solutions, and provide data infrastructure and heat tracking systems (Administrative Core); 2) identify climate-related health effects and test CCH evidence-based solutions among the most marginalized and at-risk members of society in partnership with community health workers and non-profit organizations in Boston, Madagascar, and South Africa (Research Project); 3) engage with community partners to cultivate trust, communication, and shared decision-making towards implementing community-based climate solutions that improve health inequities (Community Engagement Core); and 4) catalyze CCH implementation science and participatory research to implement and evaluate evidence-based solutions to address CCH and improve health equity by providing qualitative and quantitative analytic support, policy translation, and capacity-building initiatives for researchers and local leaders (Implementation, Solutions, and Evaluation Core). The C-EARTH leadership, research, and multidisciplinary support team brings complementary expertise in community engagement, environmental and population health research, nutrition, implementation science, cost-benefit analyses, health equity, and national and international climate policy – thus enabling transdisciplinary solutions-oriented research. C-EARTH will be instrumental in building the capacity to develop and test culturally sensitive evidence-based solutions for climate justice in high-risk and marginalized communities around the world, with opportunities for replication and scalable solutions to maximize impact.