Chronic wounds are those that fail to heal in an orderly and timely (typically three months) manner. Examples of chronic wounds include diabetic foot ulcers, pressure ulcers and venous leg ulcers. The incidence of chronic wounds is increasing as a result of lifestyle changes and the ageing population. For example, ~552 million people worldwide are estimated to have diabetes mellitus in 2030. Up to an estimated 25% of these patients will develop diabetic foot ulcers in their lifetime; half of these ulcers will be infected and 20% will undergo amputation of their lower limb. The annual economic impact of chronic wounds, which includes nursing time and dressing materials, on the global economy is estimated to be ~£20 billion by 2030. A common practise in wound management is to cover wounds with suitable dressings to facilitate the healing process. Standard dressings, however, do not provide insights into the status of the wound underneath. Thus, dressings are often changed to examine and assess the wound. This in turn hampers the process of normal wound healing and cause stress and pain to patients. The assessment process also consumes a significant amount of nursing time and dressing materials, which contributes to spiralling medical costs in wound care. In addition, current treatment methods do not use physical or chemical feedback to modify or adjust the treatment based on wound's condition, and hence have limited success. It has been proposed to embed sensors in dressings to enable clinicians and nurses to make effective diagnostic and therapeutic wound management decisions without changing wound dressings; therefore improving patient comfort. Existing sensors, however, do not satisfy the operational (e.g. sensitivity, specificity) and physical (e.g. flexibility) characteristics required for embedding them in dressings. This project will develop a sensor system to overcome these limitations. The proposed sensor system will consist of a small laser that will emit light of different colour based on the concentration of a biomarker of interest in the fluid interface at the wound surface. The change in the colour of emitted light will be measured by waving a mobile device (e.g. phone, tablet) over the dressing containing the sensor system. The captured data will be transmitted to healthcare professionals, processed, stored to keep a record of wound history, and used for diagnostics and therapeutics. The proposed project will benefit patients by effective diagnostics and treatment of chronic wounds. The information on wound condition will permit timely identification of hard to heal wounds and will also be used to create a feedback loop for fully optimised treatments tailored to individual patients. For example, the rate of release of anti-inflammatory drugs will be tailored based on wound condition. This is critical in terms of chronic wound management, where it has been shown that the longer the delay in administering appropriate treatment, the more difficult a wound is to heal.