This article provides a brief review of novel methods to evaluate postural stability in humans. Especially, I focus on the extent to which these methods can extract richer information concerning postural stability from data obtained by measuring postural sway during quiet standing (e.g., the center of pressure trajectory) than through conventional methods, which only quantify the magnitude of postural sway. Two methods are introduced. The first is a method to quantify the time-dependent pattern of postural sway using the concept of “fractal”. That the pattern extracted from the data during quiet standing is deeply associated with both the postural response to a perturbation and with the control of center of body mass during locomotion is also shown. The second is a method to quantify the spatial pattern of postural sway. I demonstrate that there is a reciprocal relationship between the angular accelerations of the ankle and hip joints in healthy young subjects and that it collapsed in elderly persons as well as when cutaneous sensation of the foot sole is reduced.