Evidence shows that children's early years are a crucial time for their development. Well-designed early childhood education (ECE) experiences can foster meaningful gains in school readiness, as well as long-term benefits such as lower rates of special education placement and higher graduation rates. The quality of early education is highly dependent on sufficient preparation and support for early educators to meet the needs of diverse young learners. Research has identified high-quality coaching as an effective professional learning practice for supporting educators in the implementation of evidence-based practices. According to the research, effective coaching relies on a strong partnership between coaches and educators; reflection and individualized feedback; focused observations; intentional coaching plans to guide sessions; and job-embedded learning opportunities for active learning. Well-qualified coaches with knowledge of specific coaching models and practices, general coaching and consultation skills, and knowledge of early childhood development and teaching are critical as well. This report examines five early childhood coaching systems--two state systems (Alabama and Washington) and three California county systems (El Dorado, Fresno, and San Diego)--that have developed systemic coaching approaches. The researchers studied these coaching systems to understand the different ways that comprehensive coaching systems can be implemented at scale, the types of coaching approaches used, and the supports offered. Although there is no singular strategy to scale effective coaching, this research provides insights for policymakers and program administrators seeking to incorporate coaching into their efforts to improve the quality of early childhood education.