In a career spanning six decades, Edward Zigler redefined developmental psychology as the equal integration of scientific inquiry and evidence with social policy formulation and analysis to improve child well-being. The theme of his accumulated work was advancing child development as social action for children and families. Besides early childhood intervention and policy, for which he devoted most of his time, Dr. Zigler did pioneering work in education and school reform, social policy, prevention, child maltreatment, family support, developmental disabilities, and in service to government. In this article, I reflect on four of Dr. Zigler's major contributions to science and society that are underrated and, in many respects, under-appreciated in the larger context of the field. These are (a) historical analysis of Head Start, (b) conceptualization and analysis of motivation as a key component of early childhood program impacts, (c) development of preschool-to-third-grade programs and school reforms, and (d) critical analysis of theory, research, policy, and practice. Together, these and other contributions by Dr. Zigler provide a strong foundation to build a better society for all.