BACKGROUND: We developed a preference assessment tool to help assess patient goals, values, and preferences for multiple sclerosis (MS) management. All preference items in the tool were generated by people with MS. The aim of this study was to evaluate this tool in a national sample of people with MS. METHODS: English-speaking patients with MS aged 21 to 75 years with access to the internet were recruited. Participants completed the preference tool online, which included separate modules assessing three core preference areas: treatment goals, preferences for attributes of disease-modifying therapies, and factors influencing a change in treatment. The tool generated a summary of participants' treatment goals and preferences. Immediately after viewing the summary, participants were asked to evaluate the tool. Rankings of preference domains were compared with rankings obtained in another study. RESULTS: In 135 people with MS who completed the tool and evaluation, the highest ranked goal was brain health (memory, thinking, brain), followed by disability concerns (walking, strength, vision). Rankings were highly similar to those in the referent study. Nearly all participants reported that the tool helped them understand their goals and priorities regarding MS and that the summary appropriately reflected what is important to them. Most participants (87%) wanted to discuss their treatment goals and priorities with their clinician. CONCLUSIONS: This preference assessment tool successfully captured patients' goals, values, and preferences for MS treatment and could potentially be used to help patients communicate their preferences to their clinician.