Research has suggested that successful adaptation to multiple sclerosis (MS) and its psychological sequelae is affected by a variety of factors, but many questions remain unanswered. This study examined the extent to which certain factors contribute to successful psychosocial adjustment. Subjects were 100 MS outpatients from several MS centers and neurology clinics in the Washington, D.C. metropolitan area. Analysis showed that the following variables contributed significantly to psychosocial adjustment: disease status (i.e., remission versus exacerbation), medication, cognitive disability, and perceived uncertainty. Coping style, social support, and perceived level of physical disability did not contribute significantly to adjustment. The findings suggest that efforts should be made to reduce patients' perceptions of uncertainty regarding their MS and that cognitive functioning be assessed and appropriately accommodated in treatment. Int J MS Care. 2004;6:98-105.