Early and aggressive treatment of rheumatoid arthritis (RA) is now regarded as best practice to limit irreversible joint damage. However, in the case of relapsing remitting multiple sclerosis (RRMS), current guidelines recommend that disease modifying therapy should only be initiated in patients with evidence of actively progressing disease. Here, the authors present the key findings of the Programme Identifying and Observing Novel Therapy Adoption in Chronic Diseases (PIONEER) study to examine the reasons for these different management approaches. Copyright © 2009 Wiley Interface Ltd