The Multidisciplinary Expert System for the Assessment \& Management of Complex Brain Disorders (MES-CoBraD) is an interdisciplinary project combining Real-World Data (RWD) from multiple clinical and consumer sources through comprehensive, cost-efficient, and fast protocols towards improving diagnostic accuracy and therapeutic outcomes in people with Complex Brain Disorders (CoBraD), as reflected in Neurocognitive (Dementia), Sleep, and Seizure (Epilepsy) disorders and their interdependence. It brings together internationally recognized experts in medicine, engineering, computer science, social health science, law, and marketing and communication from across Europe, and combines clinical information and scientific research in CoBraD with technical innovation in secure data-sharing platforms, artificial intelligence algorithms, and expert systems of precision and personalized care, with a primary focus on improving the quality of life of patients, their caregivers, and the society at large. It leverages RWD from diverse CoBraD populations across cultural, socioeconomic, educational, and health system backgrounds, with special attention on including vulnerable populations and minorities in an equitable manner and engaging key stakeholders to maximize project impact.