In the absence of red flag signs or symptoms, the diagnosis of osteoarthritis can be achieved through clinical assessment (history taking and examination). Imaging findings do not always correlate well with the patient’s symptoms, particularly in the early stages of osteoarthritis, and management is not dictated by imaging results alone. There is no gold standard for the clinical diagnosis of osteoarthritis and multiple clinical and research focussed definitions of the condition have been developed and some patients expect imaging to confirm a diagnosis. Imaging continues to be frequently used despite uncertainties about the benefit this adds to the diagnosis, the resource implications and potential for delays in commencing management. X-ray is the most common imaging used for knee osteoarthritis, however magnetic resonance imaging (MRI) is now being used more commonly to examining soft tissues and to pick up more subtle bony changes. Some healthcare professionals may use ultrasound for more superficial joints (for example: finger, toe). In some parts of the country, primary care has direct access to MRI and ultrasound scans. The aim of this review is to establish if there is additional benefit in using any imaging as an adjunct to clinical examination to diagnose osteoarthritis. This review does not seek to define when imaging is indicated in the natural history of osteoarthritis.