The major form of care for children when parents are working or otherwise not available is provided by family members, friends, or neighbors. This is especially true for children from low-income households. As policy makers have become aware of the importance of learning in the early years, attention has focused on how to support these caregivers and thus increase positive outcomes for children. This literature extends previous work and provides access to the latest findings on the effectiveness of professional development and support initiatives delivered to these home-based providers.