In these times, a book should aspire to present the most significant advances in the field, reflect the themes of the moment, and provide a useful compendium for future reference. This book accomplishes all three objectives by discussing the changing world of modern genetics in endocrine tumors and its impact on clinical practice. Clinicians have to incorporate modern genetics and systems biology in their daily practice. Educators and researchers have to introduce molecular pathways and their genetic variability in their teaching, as well as understanding of classic physiology and pathophysiology. Taking these aspects into account, the chapters in this book cover both the classic multiple endocrine neoplasia (MEN) syndromes, as well as newly described ones, such as Carney triad and Carney-Stratakis syndrome. Furthermore, the genetics of paragangliomas as well as thyroid, parathyroid, and pituitary tumors are examined. Outlining the latest research and its obvious implications for our understanding the genetics of endocrine tumor formation and molecular biology of cancer and their potential therapeutic implications, this book is not only useful for researchers but even more so for practicing clinicians, in particular internists, endocrinologists, oncologists, pediatricians, surgeons, pathologists, geneticists, and genetic counselors.