This book examines numerous topic areas that are considered to be especially relevant for making a strategic leader development investment. The topics covered are areas that have theoretical and empirical connections to important aspects of growth, change, adult development, and underlying abilities, skills, and competencies needed to lead effectively in times of great complexity. In addition, these are investment areas identified by the U.S. Army--a world-class organization faced with the need for radical transformation--as particularly relevant for success and survival. This book identifies key concerns in developing leaders and leadership, and in transforming organizations to better meet the challenges of a complex world. There are two aspects of this book that distinguish it from the numerous existing volumes on leadership in the scholarly and popular-press literatures. Most important, the overarching focus of the present book is on development. There are many offerings on the topic of leadership, but relatively few that focus on leader development--especially from a scholarly, academic perspective. Also, this volume offers a unique perspective in examining those underlying psychological competencies and processes that are viewed as especially relevant for leader development. The chapters that are collected in this edited volume were originally commissioned by the U.S. Army Research Institute as white papers to better help Army officers and researchers understand important issues in leader development. The present organization of the papers is around four central themes: a) Accelerating Leader Development, b) Cognitive Skills Development, c) Developing Practical and Emotional Intelligence, and d) Enhancing Team Skills.