Patient Empowerment through Predictive PERsonalised decision support (PEPPER) is an European Union (EU) funded research project to develop a personalised clinical decision support system for Type 1 Diabetes Mellitus (T1DM) self-management. The tool provides insulin bolus dose advice, tailored to the needs of individuals. The system uses Case-Based Reasoning (CBR), an artificial intelligence methodology that adapts to new situations according to past experience. The PEPPER system also incorporates a safety module that promotes safety by providing glucose alarms, low-glucose insulin suspension, carbohydrate recommendations and fault detection.The principal research objectives are to assess the usability, safety, and technical proof of concept and feasibility of the PEPPER in participants with T1DM. Evaluation of safety is a priority and will be assessed throughout the clinical studies. The safety components only of the PEPPER system will initially be evaluated in an out-of-clinic environment (phase 1) and will measure incidence and percentage time spent in hypoglycaemia, evaluate usability and incidence of technical faults. Following the initial safety study, the overall PEPPER system (integrated with the CBR algorithm) will be assessed (phase 2) and the primary outcome will be percentage time spent in hypoglycaemia.