High-quality preschool is one of the six key elements of the Child Parent Center (CPC) program. High-quality can be defined in many ways but the nine components described on the next page provide a picture of quality in the Child-Parent Centers. There is no consensus in the field on any one set of quality components. The CPC expansion project strives to replicate the elements and practices that have been most associated with positive outcomes in prior research on CPC and similar programs. The nine quality components described in this brief incorporate the accumulated research while remaining faithful to the CPC model. (author abstract)