The Relationship-Based Support to Home-Based Child Care assessment tool (RBS-HBCC) examines the quality of relationships and interactions between home-based child-care providers and staff specialists who support these providers at networks and other organizations. The tool is based on a conceptual model that hypothesizes high-quality support as including relationship-based, responsive approaches to meeting the needs of providers as well as the developmental needs of children in care and the work needs of families. This manual describes the development of the tool, the constructs included in the tool, how to use the tool, and guidelines for interpreting results. (author abstract)