This introductory chapter summarizes what is to follow. It indicates that the sense of human development indicated in the book’s title is a notion of overall development, rather than anything specifically to do, say, with one or another form of cognitive development. The development pictured is the sort of overall development envisaged by those like Erikson who speak of the human life cycle and of adult identity formation. But Erikson’s theory has sexist features that Carol Gilligan has deftly criticized. We need an account of the life cycle and of adult identity that works out equally for males and females (and that is clearly also applicable to gays, lesbians, bisexuals, and the transgendered), and Chap. 2 provides such an account. The final chapter, Chap. 3, speaks of what human lives in general are like. Borrowing from A.H. Maslow, R.W. White, and other psychologists, it argues that what is most pervasive of and basic to human lives is motivation that is neither altruistic nor egoistic and that places intrinsic importance on incorporating things and people outside ourselves into our lives.