Seventy-three Dutch and Flemish patients with definite multiple sclerosis (MS) were assessed by means of the Disability and Impact Profile (DIP), which is a 2 x 39 item, self-administered questionnaire with parallel questions about disabilities and their importance for or impact on the patient, resulting in a profile of weighted scores. It was designed as a tool for clinical assessment of quality of life (QoL) domains in MS patients. Group data showed more than 50% loss on weighted scores for "walk", "clean home", "work" and "worry about deterioration". In individual patients a median of 7 (range 0-23) major disruptions of quality of life (MD-QoL: loss on weighted score more than 50%) was found. Prevalence of MD-QoL in more than 10% of the patients was found for as many as 31 disabilities and > 50% for 3 ("clean home", "work" and "worry about deterioration"). Results in the MS group were compared with available data from 25 patients with rheumatoid arthritis (RA) and 25 patients with a spinal cord lesion (SCl). Weighted scores of "read", "memory" and "concentration" were significantly lower in the MS group than in the RA and SCl groups. Significantly lower weighted scores in both the MS and RA groups were found for "worry about deterioration", "physical endurance", "clean home", "work", "see" and "write". In conclusion, major disruptions in many domains of QoL were found in MS patients. Weighted score profiles for MS were in accordance with clinical manifestations. Unlike Kurtzke's Extended Disability Status Scale, DIP assesses a wide range of potentially MS-affected human activities, and also takes into account the subjective perception of disabilities.