The purpose of this research is to determine the effects of aging on the sexual behavior of female rats. Special attention will be given to possible changes in receptivity, proceptivity, and attractivity in old age. The contributions of gonadal hormones, especially estrogen and progesterone, to the display of each aspect of female sexual behavior and possible changes in behavioral sensitivity to these hormones in advancing age will be examined. Specific attributes of males, such as olfactory signals, to which young females are known to respond will be studied, and changes in responsiveness to these attributes by aging females will be determined. The common assumption that female sexual behavior does not decline with age may derive from the view that female sexual behavior is limited to receptivity. This research will test that assumption. The results will have important implications for the general concept of female sexuality in old age and for hormonal control of female sexual behavior.