Early Childhood Comprehensive Systems (ECCS) grants help states and communities improve early childhood systems to support child development, equitable access to quality services and supports, and family well-being. Truly interdisciplinary, ECCS promotes cross-sector systems change initiatives that focus on integrating health care, mental health, social services, and family support broadly and within communities with concentrated risk factors that negatively impact child health and development. Florida was 1 of 12 states funded from 2016 to 2021 to use a Collaborative Improvement and Innovation Network (CoIIN) approach to do this work. Through community-driven initiatives that focus on policy, partnerships, and practices, Florida ECCS committed to ensuring equitable opportunities for families and young children who may face barriers due to residing in disenfranchised communities. This article describes the process of evaluating this multiyear community-led, place-based initiative that leveraged cross-sector state-level support and used a variety of methods to track evolving ECCS processes and outcomes.