The Multiple Sclerosis International Federation (MSIF) was established in 1967 as an international body linking the activities of National MS societies around the world. The Federation seeks to work in worldwide partnership with Member Societies and the international scientific community to eliminate multiple sclerosis and its consequences, and to speak out globally on behalf of those affected by multiple sclerosis.

MSIF works to achieve its goal through the following key priorities:

Since its establishment in 1967, MSIF has grown to link the work of 48 member MS societies worldwide. MSIF is in touch with many other emerging societies, and aims to support all MS societies in their development. MSIF has a budget of around £2 million per year, with most funding coming from member societies, charitable foundations and fundraising campaigns. Around a quarter of its income comes from the health care industry.

In cooperation with the World Health Organization, MSIF has published the most extensive source of global data about the epidemiology of MS, the Atlas of MS. The most recent edition of the Atlas of MS was published in 2020, and shows that there are 2.8 million people living with MS globally.

MSIF supports the International Pediatric MS Study Group (IPMSSG) - a group of medical professionals from all continents working to improve the treatment of children with MS, and to undertake international research into childhood MS.

In 2020, in response to the COVID-19 pandemic, MSIF gathered MS research experts and clinicians from around the world to produce global COVID-19 advice for people with MS. This has been updated at various intervals throughout the pandemic as new evidence has emerged. MSIF collaborated with the MS Data Alliance to establish the COVID-19 and MS Global Data Sharing Initiative. This collected data on how the coronavirus impacted people with MS and the results informed the global COVID-19 advice for people with MS.