In a cross-sectional study of 117 randomly selected patients (52 men, 65 women) with definite multiple sclerosis, it was found that 76 percent were married or cohabitant, 8 percent divorced. Social contacts remained unchanged for 70 percent, but outgoing social contacts were reduced for 45 percent. Ninety-five percent lived in own house or flat and 70 percent received disablement pension. More than half of the patients (56.4 percent) were dependent on help from close relatives, most frequently spouse. The need for help, the risk of divorce, loss of contact with relatives, difficulty in going out, need for structural changes in home and need for pension became greater with increasing physical handicap. No significant differences between gender were found. It is concluded that patients and relatives are under increased social strain, when multiple sclerosis progresses to a moderate handicap (Kurtzke Disability Rating Scale, 3-5).