Interferon-beta (IFNB) is the first agent to be registered in Sweden for modifying disease course in multiple sclerosis (MS). A nationwide survey uncovered a tenfold variation between counties in the prescribing of IFNB. About 10% of patients received treatment in a few counties, while in most the figure was even smaller. No correlation was found between sales of IFNB and numbers of neurologists in the respective counties. Patients should receive treatment according to national medical guidelines, regardless of place of residence.