Our vision is that patients with knee pain receive the right treatment at the right time. In the UK, one third of people aged over 45 have sought treatment for osteoarthritis, and the disease costs the NHS over £5 billion per year. The knee is the most common site for osteoarthritis, with over four million sufferers in England alone. The aging population with expectations of more active lifestyles, coupled with the increasing demand for treatment of younger and more active patients, are challenging the current therapies for knee joint degeneration. There is a major need for effective earlier stage interventions that delay or prevent the requirement for total knee replacement surgery. There are large variations in patients' knees and the way that they function, and it is important that this variation is taken into account when treatments are developed, so that the right treatment can be matched to the right patient. Through this ambitious programme of research we will develop novel testing methods that combine laboratory-based simulation and computer modelling to predict the mechanical performance of new therapies for the knee and enable their design and usage to be optimised. Importantly these tests will take into account the variation in patients' anatomy and knee biomechanics, as well as variations in device design and surgical technique. This will enable different therapies, or different variants of a device, to be matched to different patient groups. The tools will be applied to existing treatments using clinical data to help validate that our model predictions are correct. The outcomes will better define which patients will benefit from a particular intervention and help optimise their usage. We will then apply the methods to new and emerging treatments, including regenerative devices, so that they can be tested and optimised before costly clinical trials take place. We will use these examples as case studies to demonstrate how the new testing methods can optimise the products before they reach the patient, and we will work with industry, standards agencies and regulators to promote the adoption of these methods across the sector. This programme will benefit patients, the NHS and the growing UK industry and science base that are developing new therapies for the knee.