Both skinfold anthropometry and bioelectrical impedance are indirect, simple bedside methods to assess body composition. It is not clear, however, whether the results of these methods are comparable. In this study, body composition was determined in 449 subjects by skinfold anthropometry and by bioelectrical impedance. Percentage of body fat ranged from 8.0% to 47.5% with the skinfold technique and from 0.6% to 78.5% with bioelectrical impedance. Linear regression analysis showed a significant positive correlation (r = .84; p < .0001) between the results of both techniques. However, plot analysis showed that, in comparison with bioelectrical impedance, skinfold measurements overestimate fat mass in the lower weight range and underestimate it in obese subjects. We conclude that the results of skinfold anthropometry and bioelectrical impedance are not comparable, especially in the extreme ranges of body fat. At the present time, other, more rigorous techniques are necessary to assess body composition accurately, in the extreme ranges of body fat in particular.