The second edition of the Endocrine System volume of the Netter Collection is designed to provide physicians at all stages of training and practice with a visual guide to the anatomy, physiology, and pathophysiology of the endocrine glands. The first edition was published in 1965. In the intervening 5 decades, there have been remarkable developments in our understanding of endocrine disorders. The text has been entirely rewritten, but most of the anatomic and clinical artwork of Frank H. Netter, MD, has stood the test of time. Since new endocrine disorders and treatment approaches have been recognized over the past 50 years, new artwork has been added in every section, including the following: current surgical approaches to remove pituitary tumors, tests used in the diagnosis of Cushing syndrome, adrenal venous sampling for primary aldosteronism, Cushing syndrome caused by primary pigmented nodular adrenocortical disease, treatment of type 1 and type 2 diabetes mellitus, multiple endocrine neoplasia types...