Advances in knowledge of child development, gained through the in-depth study of healthy infants and children, as well as through observations of deviations or delays in development, have provided the primary care physician (PCP) with the conceptual framework and the empirical knowledge needed to deal effectively with the mental health needs of children and families.

Underlying this work is the core construct of developmental plasticity, which emphasizes the flexibility of the developing child in adapting to biological and environmental challenges such as low birth weight, injury, or medical illness.[1] Growing awareness of the extent to which the environment influences gene expression through different mechanisms further emphasizes the plasticity of development.[2] Another contributing factor is increasing understanding of the importance of the ecologic context in which the child is raised and how attention to various levels in the ecologic context, such as developing programs and policies to support families, can have a positive influence on development.[3] The very architecture of a developing child's brain is profoundly shaped by environmental influences, and these influences, in turn, are amenable to intervention.[4] [5]