Postural stability was measured in 100 healthy people by a quantitative, computer calculated Romberg's test. The persons were aged 20-69 years, and a table of normal ranges is provided. Older men are found to have higher sway figures than young men, while this was not significant in the group of women. In a second part of the study the reproducibility of the method was studied in 10 healthy people. Sway was measured twice a day during 5 consecutive days of work. No significant alterations in the sway measurements were found. The individual variation coefficients ranged from 11-29% (mean value: 18%). By the present study it is concluded that the quantitative Romberg's test is a reasonable way of measuring postural stability.