The effects of aging on Postural sway in upright and forward lean stance were investigated. Postural sway was measured on a center of gravity apparatus using two age groups of female subjects 20 to 30 years old and 70 to 80 years old. The older adults demonstrated significantly larger sway areas than the young adults in both stance positions. The patterning of the center of gravity projections on the base of support tended to be similar under all conditions except in the young adults/upright position where the antero-postero excursion was larger than the medial-lateral. The mean locations of the center of gravity projections were often posterior and to the left of the geometric center of the base of support. The distance between the two points was least in the older adults/forward lean position, i.e., the experimental unit which demonstrated the largest area of sway.