Osteoarthritis (OA) biomarkers that can measure and predict the full spectrum of disease progression and outcomes are needed, but few, if any, such biomarkers have been validated for this purpose. The Osteoarthritis Research Society International (OARSI) has organized an OA Biomarkers Global Initiative. As a part of this Initiative, three workshops have been planned to occur over the next 4 years to focus on identifying and removing obstacles to progress in the field and planning the way forward. In addition to OARSI, the National Institute of Arthritis, Musculoskeletal, and Skin Disease, the Arthritis Foundation, the Orthopaedic Research Society, and the American Orthopaedic Sports Medicine Society cosponsored the first meeting April 23-24, 2009. Organizers brought together thought and research leaders in the field, young investigators, biomarkers researchers with insights from other fields, clinical investigators with a responsibility for OA sample and resource management, funding agencies, and commercial entities with an interest in the commercial propagation as well as the application of markers in OA.