ABSTRACT The Green Heart Project is a rigorously defined clinical controlled trial on the effect of residential vegetation on cardiovascular health and disease risk. The project evaluates cardiovascular health and disease as well as neighborhood characteristics before and after increasing greenspaces in neighborhoods in Louisville, Kentucky. The results of this project will elucidate the contribution of greenness to cardiovascular health and provide new insights into the effects of urban vegetation on community environments. These findings will be directly relevant to the development of new public health policies and optimization of ongoing planting efforts in cities around the world to enhance public health. Collectively, the Green Heart Project will contribute to the formulation of an imitable paradigm, a model that could be readily replicated in other cities in both developed and developing countries. The proposed diversity supplement (parent grant R01 ES029846-03) will support a junior-level assistant professor, Dr. Natasha DeJarnett, who is an environmental health researcher with expertise in air quality, climate-health, and cardiovascular disease risk. This diversity supplement will contribute to the proposed Green Heart Project by strengthening its community engagement and outreach activities and by providing additional input into its neighborhood characteristics assessment. Meaningful participation of community members in activities that affect their environmental health is key toward achieving environmental justice and avoiding unintended consequences, like gentrification and displacement. Dr. DeJarnett’s experience with stakeholder engagement at national membership associations and her passion for health equity ensure that she will be a strong contributor toward effective community engagement, collaborating with members of the community, and collecting community-informed data. Dr. DeJarnett’s expertise in air quality and climate adaptation will expand the robustness of the air quality assessment in the parent grant by incorporating local temperature gradients, a key factor of air quality. Examining temperature gradients through a lens of equity will more accurately define the relationship between greenness, air quality, and cardiovascular health. Thus, the overarching hypothesis of the supplement is that equity-informed temperature gradients and expanded data collection of community perceptions on equity will enhance the air quality and community assessments to better explain the relationship between increasing greenness and resulting air quality and cardiovascular health outcomes. The specific aims are to: 1. Support the community engagement initiatives of the Green Heart Project and develop new approaches to community engagement and assessment, and 2. Examine how an increase in area greenness affects temperature gradients within an urban neighborhood. Successful completion of these aims will enhance and enrich the parent project, whil...