Minnesota Symposia on Child Psychology: Volume 5 was first published in 1971.This volume, like the previous volumes in this series, is based on the papers given at an annual Minnesota Symposium on Child Psychology sponsored by the Institute of Child Development at the University of Minnesota. The content of this book is based on the papers of the 1970 symposium. For each symposium a number of outstanding child psychologists are invited to present papers dealing with their respective programs of research.Six papers by ten contributors are published here: “The Role of Modalities in Perceptual Cognitive Development” by Jacqueline J. Goodnow, George Washington University; “Hypnosis and Childlikeness” by Ernest R. Hilgard, Stanford University; “Explorations into Patterns of Mental Development and Prediction from the Bayley Scales of Infant Development” by Jane V. Hunt and Nancy Bayley, both of the University of California, Berkeley; “A Dyadic Analysis of ‘Aggressive’ Behaviors” by Gerald R. Patterson and J. A. Cobb, both of the Oregon Research Institute; “Development of Hierarchical, Configurational Conceptual Models for Parent Behavior and Child Behavior” by Earl S. Schaefer, National Institute of Mental Health; and “Some Aspects of the Development of Space Perception” by Seymour Wapner, Leonard Cirillo, and A. Harvey Baker, all of Clark University.