The vulnerability framework developed by the Intergovernmental Panel on Climate Change (IPCC) defines vulnerability as a function of exposure, sensitivity, and adaptive capacity. Building off this framework, the Connecticut Institute for Resilience and Climate Adaptation (CIRCA) developed a Climate Change Vulnerability Index (CCVI) for the state of Connecticut, designed to integrate flood and extreme heat-related climate exposure with impacted socioeconomic, infrastructure, and ecological variables into a single comprehensive index that can guide resilience planning and prioritization at multiple levels. The index serves as a central component of the Resilient Connecticut project, a statewide initiative to advance climate adaptation and resilience planning through data-driven tools, community engagement, and strategies to address flood and heat risks across vulnerable communities. In this article, we detail the development of the CCVI, including earlier iterations, methodology, stakeholder engagement activities, and lessons learned that can impact resiliency planning in Connecticut. Preliminary statistical analyses, notable regional trends, data limitations, and future areas for research advancement are also discussed. The CCVI framework detailed here can be used in the process of identifying priority areas for intervention and supporting the selection and design of targeted resilience projects, and can also be adapted for other states.