In this interdisciplinary study of the human life course as a unit, scholars examine aspects of the life course, looking at several features over a short span and at a few traits over a longer period. provides an overview from disciplines (e.g., history, demography, sociology) that are concerned with understanding the human life course; contains studies of special populations in which integration of a variety of experiences over time can be accomplished. Based on these approaches, new methods appropriate to a science of human life are proposed and discussed in a form suitable for students, faculty, and professionals in human development (sociology, anthropology, psychology), demography, and gerontology.