Based on previous studies, we hypothesised that during the pandemic changes in the PA behaviour of pwMS are associated with a range of demographic, clinical and socio-behavioural factors. Using data from an international cross-sectional online survey-based study initiated by the Special Interest Group for Mobility of Rehabilitation in MS (RIMS) involving an international team of physiotherapists and researchers from Australia, Belgium, Ireland, Israel, Italy, Norway, Serbia, Spain, Turkey, the Czech Republic and United Kingdom, we sought to answer 3 key research questions about activity levels of pwMS during the COVID-19 pandemic.