The previous edition of The Bethesda System for Reporting Thyroid Cytopathology provided important updates and advances in the practice of thyroid cytopathology. It was inspired by new developments in the field of thyroid cytopathology since the publication of the first edition in 2010. These included revised clinical guidelines for the management of patients with thyroid nodules, the introduction of molecular testing as an adjunct to cytopathologic examination, and the reclassification of the non-invasive follicular variant of papillary thyroid carcinoma as non-invasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP). This new third edition provides updates to the current reporting terminology and diagnostic criteria, including new information on ancillary molecular testing, as well as imaging findings and clinical management. This book provides a more unified approach to diagnosing and reporting thyroid FNA interpretations. It simplifies the reporting structure by settling on just one name for each of the six categories and aligning terminology with the most recent classification of thyroid tumors by the World Health Organization. Written by experts in the field, The Bethesda System for Reporting Thyroid Cytopathology, Third Edition  aims to inspire advances in thyroid cytopathologic diagnosis and the betterment of patients with thyroid nodular disease. It serves as a reference guide not just for pathologists, but also endocrinologists, surgeons, and radiologists.