Age is a complex cross-cutting notion for at least two reasons: the intricate interweaving of its biological and socio-cultural meanings and its dual significance as both a benchmark in an individual's life course and a foundation for social structure. This book offers new perspectives on age and ageing by combining achievements in the biological sciences and their different applications and interpretations in demography, anthropology, psychology and other pertinent disciplines. Thirty contributors from these various fields revisit the measures and the biological models of ageing, the borderline between normal and pathological ageing, the pertinence of chronological age as a benchmark along the life course, its interrelations with psychological development, with reproductive phases and other life events, the « normalizing role ascribed by age classes and the risk of falling into ageism, the cross-cultural diversity and temporal changes of its meanings, the gender divide (real and perceived), as well as the rights that should be enjoyed at each age.