This volume creates a bridge across cognitive development and cognitive aging. Pairs of researchers study the rise and fall of specific cognitive functions, such as attention, executive functioning, memory, working memory, representations, language, problem solving, intelligence, and individual differences to find ways in which the study of development and decline converge on common processes and mechanisms. The contributed chapters are framed by an introduction that sets out the problems to be discussed and a conclusion that extracts the common themes and speculates on the implications for theory building. The book is unique in offering a lifespan approach to cognition by experts in the individual facts of cognitive functioning from either the developmental or the aging perspective.