QUESTIONS UNDER STUDY: This study aims at estimating the costs of disorders of the brain in Switzerland based on the published epidemiological and economic evidence. Methods: the data presented for Switzerland are derived from the "cost of disorders of the brain in Europe" study of the European Brain Counsil (EBC). Available Swiss data were integrated. RESULTS: There are an estimated 2 million people currently living with a brain disorder in Switzerland. This number amounts to about 25% of all people living in Switzerland. The total annual costs are estimated to amount to 8.9 billion Euros corresponding to 1200 Euros per inhabitant and per year. Direct medical expenditure accounts for 33% of all expenditure, while indirect costs add up to 49%. Mental disorders account for approximately 2/3 of the total costs of brain disorders, ie, 5.6 billion Euros. This cost estimate comes very close to the current expenses for mental health in Switzerland with 5.3 billion Euros constituting 16% of total health care costs. : The present study probably underestimates the full economic burden of brain and especially mental disorders in Switzerland. In order to better understand the impact of brain disorders on Swiss society prospective field studies are needed in all disorders of the brain.