This study examined how partnerships between early care and education providers were developed and how they worked together to deliver comprehensive, high-quality services to infants and toddlers from low-income families. Survey data were collected from 220 Early Head Start (EHS) program directors and 386 child care center directors and family child care providers participating in EHS-child care partnerships. Research Findings: Nearly half of EHS programs chose partners with whom they had prior relationships, and most engaged them early (often before receiving the grant). Both EHS programs and child care providers described their relationships as mutually respectful and focused on similar goals. Through the partnerships, child care providers had access to professional development opportunities and offered children and families comprehensive services, such as health screenings. Practice or Policy: This study provided a nationally representative picture of EHS-child care partnerships. The findings suggest that strong relationships are foundational to the implementation of early care and education collaborations aimed at expanding access to high-quality care for infants and toddlers from low-income families. Collaborations are a potentially important policy lever that can help support the expansion of high-quality early care and education. (author abstract)