This book offers a comprehensive guide to thyroid fine needle aspiration (FNA) cytology. Borderline/precursor tumors, which were introduced in the 4th edition of the WHO classification of thyroid tumors, are also incorporated. In this second edition, prominent international experts discuss the different approaches to thyroid FNA cytology employed in various countries such as Australia, Canada, China, Korea, Portugal, Switzerland, Taiwan, Thailand, Turkey, Ukraine, the USA, UK, Italy and Japan. The book not only covers key principles of thyroid cytopathology but also addresses technical aspects such as procedural complications, liquid-based cytology, immunocytochemistry, staining procedures, and potential pitfalls. Case-based descriptions and clinical findings, radiologic imaging, cytology, and histopathologic diagnosis – all complemented by a wealth of detailed photographs – will help reader understand and overcome many common dilemmas in daily practice. As such, the book represents an indispensable reference work for all cytopathologists, especially those practicing thyroid cytopathology.