Marianne de Visser, MD, Academic Medical Centre (AMC), University of Amsterdam, Amsterdam, The Netherlands, comments on the traditional outcome measures in motor neuron diseases and neuropathies. In amyotrophic lateral sclerosis (ALS), the most commonly used metrics are measures of function and survival, including muscle and respiratory strength and tracheostomy-free survival. Nevertheless, these measures require large sample sizes and long-term follow-up, which is a major challenge due to the short life expectancy of patients with ALS. It is therefore essential to identify biomarkers able to predict prognosis and response to treatment. Prof. de Visser also outlines recent developments in drugs increasing the amount of survival motor neuron protein (SMN) in children with spinal muscular atrophy (SMA). Trials investigating the efficacy of this drug used physiotherapy outcome measures that appear to be reliable. Finally, Prof. de Visser explains that patient-related outcomes such as quality of life (QoL) are increasingly included in study designs. This interview took place during the XXV World Congress of Neurology.