The Child and Adolescent Thyroid Consortium (CATC) Biorepository is a collaborative research program dedicated to studying thyroid cancers and other thyroid-related conditions. The goal of the CATC Biorepository is to address the unmet need of creating a well-annotated registry and bio specimen repository for patients with varying thyroid-related diagnoses. Collaborating clinicians and scientists are encouraged to use the specimens and infrastructure of the CATC Biorepository to make meaningful discoveries to help patients most at-risk.