Project Summary Climate change health risks can be reduced through mitigation and adaptation interventions, with research required to determine which interventions to prioritize where, and how to implement them rapidly, effectively, and at scale. The goal of the Implementation and Evaluation (I&E) Core of the REACH Center is to support investigator-driven research that leverages implementation science to understand and improve the uptake of evidence-informed innovations that reduce the health consequences of climate change at scale, including in public health practice, healthcare and community settings. The I&E Core will work with academicians, as well as public health, healthcare and community implementers, to achieve its goal through a combination of peer-to-peer learning, training, and co-production of climate-relevant implementation science projects. The University of Washington REACH Center is ideally situated to link implementation science research with public health and healthcare organizations in the region. Our faculty is at the forefront in defining multidisciplinary, implementation science research methods, and has developed novel training curricula in public health, healthcare and implementation science. Furthermore, REACH-affiliated investigators lead diverse programs to implement and scale-up health innovations. To support the overall goals of the REACH Center, the I&E Core proposes a package of high value training and community of practice opportunities, as well as technical consultations on implementation science, to lead to new and innovative research, and ultimately improve the speed, efficiency, and quality of efforts to translate scientific evidence on reducing the health consequences of climate change into effective, large scale health programs. The I&E Core’s specific aims are to: 1) Develop a cohort of climate and health I&E Fellows to assess contextual determinants, successful implementation strategies, and/or implementation outcomes of evidence-informed climate and health interventions; and 2) provide training and technical assistance for researchers on implementation science in climate change and health. Under aim 1 we will pilot an 18-month I&E fellowship program that will recruit and engage teams of academicians, regional public health practitioners, healthcare leaders, and/or community-based organizational leaders who will work in tandem with Core faculty to design and implement a climate change and health implementation science project. Under aim 2 we will adapt an intensive implementation science training institute to include climate change and health content and will support attendees at this course; will host quarterly webinars on the intersection of implementation science, climate change and health research; and will provide technical consultations for emerging and established investigators on implementation science methods.