Many people with multiple sclerosis MS (PwMS) have impaired balance and walking, and fall frequently. High-quality measures of imbalance and fall risk are essential for identifying who may benefit from interventions to improve balance and prevent falls, and for selecting the most appropriate interventions. We recommend the International Classification of Functioning, Disability and Health (ICF) model. Many measures are available to assess factors affecting balance, fall risk, and walking at the different levels of the ICF. Combining these measures provides the most complete assessment of the individual and the best guidance for interventions by the health care team.