Although normally thought of as a sex hormone, recent research has highlighted the numerous and significant effects that oestrogen has on the CNS, extending far beyond its important reproductive role. It has been shown that oestrogen acts as a neural growth factor with important influences on the survival, plasticity, regeneration and ageing of the mammalian brain. This exciting book brings together leading clinicians and researchers to discuss oestrogen’s basic mechanisms of action, the extrahypothalmic brain regions it affects, and its influence on cognitive functions in animals and humans. Finally, recent research on the role of oestrogens in ageing and dementia, including the significance of oestrogen action in Alzheimer’s disease, is discussed. The 15 papers contained in this book, together with the extensive discussion sessions that follow them, reveal much new and exciting work in this area, and identify promising new research directions.