Gonadal hormones, most notably oestradiol, enhance some aspects of cognitive function in animal and human models. However, the demonstrated effects are often not large and inconsistent across studies. Nonetheless, because increased numbers of women are living longer in a state of oestrogen deprivation, research on this topic continues to be important. This review traces major developments concerning hormonal influences on cognition and provides some insights from recent studies that may be fruitful for future research.