1 To be published in Russian in N. I. Chuprikova & E. V. Volcova (Ed.), Differentiation- integration theory of development: Philosophical interpretation and application to psychology, linguistics, and education. Moscow: Institute of Psychology RAS Explicating Developmental Reconceptualization: Differentiation and Integration in Intellectual Development Andreas Demetriou 1 , George Spanoudis 2 , Michael Shayer 3 , and Smaragda Kazi 4 1. University of Nicosia, Cyprus 2. University of Cyprus, Cyprus, 3. Kings College, University of London, UK 4. Panteion University of Social Sciences, Greece, Special thanks are due to Robert Kail, Deanna Kuhn, David Moshman, Jerry Carlson, Philip David Zelazo and two anonymous reviewers for their useful comments on earlier versions of this paper. Address: University of Nicosia Research Foundation, University of Nicosia, Makedonitissas Avenue, P.O. Box 24005, 1700 Nicosia, Cyprus Email: ademetriou@ucy.ac.cy or demetriou.a@unic.ac.cy