Due to the aging population in the Western world, osteoporosis has become a major problem which is of interest to several medical disciplines: not only radiologists but also gynecologists, endocrinologists, rheumatologists, and orthopedic surgeons are involved in the management of this widespread condition. Functional imaging is becoming rapidly an important area of diagnostic radiology. Imaging of osteoporosis is another application of this recent addition to the armory of radiology. It is important that radiologists should be fully aware of the range of diagnostic modalities-conventional radiologic methods, dual X-ray absorptiometry, quantitative computed tomography, quantitative ultrasound, magnetic resonance imaging, etc. -that are now available for the diagnosis and the follow-up of osteoporosis, and know how to apply these sophisticated methods in daily clinical practice. Dr. S. Grampp is a radiologist with a longstanding interest in osteoporosis, and his previous publications on this condition are internationally known. He has been very successful in engaging several outstandingly qualified experts to contribute to the indi­ vidual chapters of this superb book, which provides a omprehensive c overview of our current knowledge of osteoporosis. I am confident that this volume will meet with great interest from radiologists and all other clinicians involved in the care of patients with osteoporosis and will encounter the same success as many previous volumes in this series.