Early intervention (EI) and early childhood special education (ECSE) practitioners participating in the Child Outcomes Summary (COS) process must understand age-expected development, the ages at which children typically acquire different skills. This resource provides answers to commonly asked questions about age anchoring as it applies to the COS process. It is designed as a reference for practitioners, as well as supervisors, coaches, and professional development staffs. It offers guidance on how to accurately age anchor a child's functional skills and explanations of how that guidance applies to COS teams. Using the guidance will help practitioners age anchor for the COS in a time-efficient manner while also gathering the rich information needed to complete a high-quality process.