The Pituitary, Fifth Edition continues the tradition of a cogent blend of basic science and clinical medicine. The comprehensive text written by expert pituitary scholars is devoted to the pathogenesis, diagnosis and treatment of pituitary disorders. The new fifth edition has been extensively revised to reflect the most recent data on new research advances in tumorigenesis and new therapeutic approaches for pituitary tumors, particularly in acromegaly and Cushing disease. Notably, new chapters devoted to the Pituitary-Immune Interface and Pituitary Radiotherapy have been included, along with a chapter on Aggressive Pituitary Adenomas developed to align with the WHOs Classification of Pituitary Tumors. Furthermore, new authors have been invited, ensuring a fresh perspective on critical issues in the field. This extensive body of knowledge is useful for students, trainees, physicians, and scientists who need to understand critical pituitary functions and how to care for patients with pituitary disorders.