Osteoarthritis (OA) is becoming a significant problem worldwide. Pain and loss of joint function have a major impact on an individual’s quality of life and through loss of time at work and increasing health care costs has a significant economic burden on society. OA is a complex disease with a number of known risk factors. There is variable involvement of the synovial joints in populations as a result of both environmental and genetic factors. Recent candidate gene studies and genome-wide association studies are beginning to identify known and previously unsuspected genes to be associated with the development of OA. These studies raise the exciting prospect of future stratification of patients into genetically identified sub-groups that may have specific targetable pathways for disease management.