Metabolic Bone Disease and Clinically Related Disorders. Louis V. Avioli and Steven M. Krane, Editors. Academic Press, San Diego, California, U.S.A., 1998. Metabolic Bone Disease and Clinically Related Disorders is a multiauthored book, now in its third edition (published some 8 years after the second edition). This volume has become the definitive comprehensive book in the area of metabolic bone disease and is thus an important textbook. The first edition (1977) was much shorter and contained only 7 chapters. In the current edition, 26 chapters cover all the fundamental metabolic bone disorders of humans, and each chapter is written by a senior authoritative figure in the field of divalent mineral metabolism and calcium endocrinology. The explosion of new information concerning bone formation and remodeling is comprehensively and effectively reviewed. The first 10 chapters cover calcium, phosphorus, and vitamin D metabolism and their biologic functions with several chapters emphasizing direct approaches to bone development and a better understanding of bone mineral measurement. From Chapters 11–26, a variety of metabolic bone diseases are discussed in depth. In contrast with previous editions, the current edition includes expanded information regarding the molecular biology of both normal bone and of human disorders of bone. A number of key figures in the field of molecular biology related to bone metabolism, especially Drs. Edward Brown, Eduardo Slatopolsky, David Rowe, Greg Mundy, Mike Econs, and Francis Glorieux have written up-to-date chapters regarding the entirety of disorders that affect bone and mineral desposits. Chapter 18, entitled “Bone Disease and Hyperthyroidism,” by Douglas S. Ross is a particularly useful chapter because few textbooks of endocrinology or bone disease discuss the full spectrum of hyperthyroid bone disease. Another important contribution is Chapter 22, “Hypercalcemia of Malignancy” by Dr. Gregory Mundy. This chapter contains the latest information regarding the remarkable story of the hypercalcemia of malignancy which has evolved so dramatically over the past 20 years. Dr. Mundy has interwoven the effect of various interleukins in the stimulation of osteoclasts. This chapter presents a most complete and compelling story regarding this serious complication of malignancy. In the third edition of Metabolic Bone Disease, Avioli and Krane have greatly expanded the information in a number of areas in the textbook itself. It is more thorough and broadly composed than the two previous editions. In summary, this text is useful in acquiring a deep knowledge of metabolic bone disease. Its greatest strength is the experience and contributions of the various authors of the chapters, many of whom have been in the field of metabolic bone disease for more than 30 years. In addition, it contains a great deal of information concerning the molecular biology of various conditions which has greatly enhanced this edition of the book. Certainly it should be on the shelf of all physicians who care for patients with metabolic bone disease, be they nephrologists, endocrinologists, or oncologists.