An aim of many students of human development is to penetrate behavioral variability in such a way as to reveal stable phenomena. This broad aim is challenged on numerous fronts when researchers study infant behavior, for students of infants are everywhere confronted with variability. But, in the context of research, variability of subjects'…

Presents an account of the development and use of the Neonatal Behavioral Assessment Scale (NBAS). Discusses ways in which NBAS has increased understanding of development in the newborn, of states of consciousness in the infant, of prediction in development, and of a clinician's opportunities to share information with parents. (BC)