Although there is increasing interest in measuring the quality of life (QoL) of people with multiple sclerosis (MS), relatively little is known about the issues of importance to people severely affected by MS. In the first of two systematic reviews, we searched the literature to identify measures that have been used to assess health-related QoL in people with MS, and described their measurement properties in terms of validity, reliability, responsiveness to change, and appropriateness for QoL assessment in people severely affected by MS. In the second review, we identified care domains important to people with MS, by reviewing survey, focus group and interview studies involving people with MS and/or their caregivers. Forty-six studies evaluating 12 disease-specific and ten generic QoL measures for patients, and one disease-specific measure for caregivers, satisfied all inclusion criteria. Sixteen focus group or interview studies and 51 questionnaire-based studies evaluated domains of care important to people with MS, and seven qualitative and 11 questionnaire-based studies assessed domains of care important to their caregivers. From these studies, we identified 15 domains of care important to people with MS and 12 domains important to caregivers. QoL measures differed markedly in their coverage of these care domains. Moreover, each measure fulfilled some but not all criteria of validity, reliability, responsiveness, and appropriateness. Further work is needed to clarify the domains of care relevant to people with severe MS, and to measure health-related QoL in this population.