Osteoarthritis is the most common joint pathology which primarily affects the older population. The disease is characterized by unique pathological changes in some synovial joints, predominantly affecting the articular cartilage, but also entire joints, including the synovial tissue and subchondral bone. The growth of research on normal and abnormal biology of tissues in the articulating joint, including the application of novel molecular biological approaches and new imaging techniques, is reflected in this volume. It describes the current state of knowledge and helps to further understand the etiopathology of osteoarthritis, hopefully leading to early detection of the disease and novel treatment modalities. The volume contains contributions and discussions from a select group of investigators, all experts in this field, who met at the conference The Many Faces of Osteoarthritis , held in June 2001 at Lake Tahoe, to acknowledge Klaus E. Kuettner and his contributions to osteoarthritis research. The book is intended as a source of information for researchers as well as for clinicians working in the fields of bone and joint surgery, tissue engineering, orthopaedics, rheumatology and biomedicine