Emerging Themes in Cognitive Development presents two volumes of the newest research and theory in cognitive development available at the outset of the 1990s. These ideas are firmly rooted in research from the 1980s and, in some sense, these volumes represent a culmination of that research and of even earlier work. Nevertheless, these volumes are offered as catalysts more than summaries, because each presents the freshest and most recently gathered data of many scientists whose insights have had an important impact on the field. The latest ideas of these researchers will, in some cases, immediately prove to be dominant themes of research and theory. In other cases, of course, it will take longer for the concepts presented to capture the imagination of students and colleagues who are still invested in meritori ous research on other themes. In either case, the syntheses and innova tions proposed are not likely to escape the careful study of the serious scholar, and it is to such scholars that these volumes are dedicated."

Emerging Themes in Cognitive Development, Volumes I and II offer the full spectrum of current knowledge and research trends in cognitive developmental psychology. The first volume provides a foundation by describing key discoveries in new areas of research and by thoroughly examining fundamental aspects of the field, including several demonstrations of formal modeling; the gains in prediction and precision that can be won by such mathematical analyses are the hallmark of cognitive development as a maturing science. The second volume traces the development of cognitive competence - denoting a change or increment in cognitive proficiency, understanding, or mastery - and includes analyses of innovative and previously unpublished studies. The primary challenge issued by many of the authors in this volume is to ensure the incorporation of new knowledge into educational practices. These volumes, which are milestones in cognitive developmental psychology, interest every researcher in the field.