ABSTRACT
This chapter discusses the meta-theoretical and theoretical bases of an approach to the study of adolescent development that takes as its initial target of developmental analysis the idiographic characteristics of the developing person. To fully implement this idiographic approach to the description, explanation, and optimization approach to youth development will require broad-based multidisciplinary, multi-professional, and public–private collaborations. Developmental scientists using an relational developmental systems-based, non-ergodic frame for their youth development research may make foundational contributions to this collaboration. In contrast to the theoretical and empirical scholarship about nomothetic and differential patterns of adolescent development that have marked, and that continue to mark, the adolescent development literature, there has been no theoretical model offered about the idiographic patterns of adolescent development. In both the socio-emotional and cognitive developmental areas of adolescent development, classical stage theorists have emphasized that all people pass through a series of qualitatively different stages in a fixed, invariant sequence; people cannot skip or re-order stages.
