For a quarter of a century, ECTRIMS and ACTRIMS have served as the both world’s largest professional organisations dedicated to the understanding and treatment of Multiple Sclerosis. The European and American Committees for Treatment and Research in Multiple Sclerosis (ECTRIMS and ACTRIMS) are independent representative world-wide organisations devoted to multiple sclerosis (MS). To facilitate communication, create synergies, and promote and enhance research and learning among professionals for the ultimate benefit of people affected by MS. Both organisations work with researchers and clinicians of the member countries and with other organisations that share similar missions and objectives on a worldwide scale, creating networking and collaboration opportunities. The ultimate goal of ECTRIMS and ACTRIMS is to improve basic and clinical research and clinical outcomes in MS.