Brain health is a rapidly expanding field. WHO’s position paper on optimizing brain health across the life course is a technical complement to the recently-adopted Intersectoral global action plan on epilepsy and other neurological disorders 2022–2031. Many determinants are known to affect brain health at different stages of life. The position paper provides a conceptual framework for what brain health is and how brain health can be optimized throughout life with actions across the following clusters of determinants: physical health, healthy environments, safety and security, learning and social connection, and access to quality services. Optimizing brain health can not only reduces the prevalence and burden of neurological disorders, but also improve mental and physical health overall and create positive social and economic impacts, all of which contribute to greater well-being and help advance society, irrespective of the presence or absence of disorders.