Orthopaedic surgeons treat a wide variety of patients with cartilage damage, from young athletes with cartilage injury to elderly patients with advanced osteoarthritis. There are a variety of treatment options, and these are chosen based on the age of the patient. For patients under the age of 35, biological repair is successful. Biological repair includes techniques that try and make the cartilage heal itself by stimulating regenerative cells from the underlying bone (microfracture) or removing healthy cartilage cells from a non load bearing part of the joint, growing them in the laboratory, and re-implanting in the defect. For older patients, total or partial joint replacement is more reliable. The average age of total hip and knee replacement patients in the UK is 69 and 70 years respectively, and these have remained constant over the past five years indicating no trend for surgeons to replace joints of younger patients. There is therefore a wide gap in the treatments available for patients in the 35 to 60 year age bracket who are considered too old for biological repair, but too young to be considered ideal candidates for joint replacement. The aim of the fellowship is to develop the technology for patients in this age group that can replace the cartilage surface without removing bone stock such that any future partial or total joint replacements can be performed as a normal index procedure. To achieve this aim, the fellowship will use advanced materials and manufacturing techniques to create the technology required for cartilage substitution implants with ultra low friction and wear properties that will protect the device from the service loads it will experience in use. In addition to providing the orthopaedic surgeon with a treatment option for the 35-60 year old patient, developing this technology will have application across the whole orthopaedic field. It will generate the mechanical boundary conditions and test methods for further development of biological repair scaffolds and repair material (currently mostly fibrocartilage rather than the desired hyaline cartilage) for patients under 35 years old. The development of polymer technology will provide the information required for low cost all polymer implants that would be suitable for less functionally demanding patients. The manufacturing methods may also be suitable for interpositional implants with tailored frictional properties and morphology to prevent dislocation. Each of these themes will be pursued within the fellowship.