The Centenary of the American Thyroid Association (ATA) was celebrated in 2023, and I was honored to present the “Year in Thyroidology: Basic Science” Lecture at the 92nd Annual Meeting of the ATA in Washington, DC. All basic science papers in the fields of thyroid gland development and function, thyroid autoimmunity, thyroid cancer, and thyroid hormone action published between September 1st, 2022 and August 31st, 2023 were considered. Searches of PubMed® (https://pubmed.ncbi.nlm.nih.gov) and bioRxiv (https://www.biorxiv.org) identified over 2500 articles. Initially, 100 of those considered to be the most impactful were selected based on their novelty, scientific rigor, general interest, and application of cross disciplinary, state-of-the-art methods. Forty-five papers were selected for in-depth scrutiny. Ultimately, 5 were highlighted in the presentation and a further 10 were discussed (Table 1).