The potential capacity of the biphosphonates to intervene in osseous remodeling was recognized more than 30 years ago. The biphosphonates inhibit osteoclastic activity. In spite of advances in early detection, surgey, chemo-and radiotherapy, metastatic bone disease is still a major and in many cases intractable clinical problem. The biphosphonates are now the most effective agents in the management of bone metastases - as shown by trials in patients with breast and prostate cancer, and in multiple myeloma. Bone pain, new ostelytic events and pathologic fractures are decreased and complications associated with these events are avoided. Existing osteolytic lesions may even be reversed. New fields of indications of biphosphonates are shown to be in the adjuvant therapy of breast cancer and in stage 1 multiple myeloma to prevent skeletal destruction and also to inhibit tumor growth. Over the past few years the biphosphonates have proved their value also in many other conditions such as Paget's disease of bone, osseous disorders with an osteoclastic component leading to osteopenia/osteoporosis, in congenial, endocrine and metabolic disorders. Perhaps, for the future and for the next millennium the most widespread and extensive use to these anti-osteoclastic component leading to osteopenia/osteoporosis, in congenial, endocrine and metabolic disorders. Perhaps, for the future and for the next millennium the most widespread and extensive use to these anti-osteoclastic agents will be in these disorders, and particularly in so-called primary osteoporosis which evenually effects anyone who lives long enough, causing widespread morbidity with drastic economic consequences both individually and nationally. The authors' aim is to provide an office and desk companion - comprehensive, concise, practical for easy reference - an up-to-date guide for prevention and therapy of skeletal complications whenever and wherever they occur in general and specialized medical practice.