Jean Brittain Leslie is a senior fellow and director of strategic initiatives in the Global Leadership & Analytics Group at CCL. In this role, she develops, oversees, and helps implement programs, projects, and processes that support leadership research and analytics' vision and short- and long-term plans. Jean has published more than 100 pieces on leadership, assessment, and feedback-in the form ofpeer-reviewed articles, popular-press articles, book chapters, and books. She has an MA in sociology from the University of North Carolina at Greensboro. Michael John Peterson, at the time the original sourcebook was published, was a doctoral candidate in the educational psychology, measurement, and evaluation program at the University of North Carolina at Chapel Hill. In this program, Michael conducted research on topics ranging from leadership to cognitive and motivational psychology and the cognitive neuroscience of emotional processing. He has a BS in physics from the University of Minnesota at Minneapolis and an MS in gifted education from Northeastern Illinois University. John W. Fleenor is a senior fellow and a senior researcher in product development at CCL. He is responsible for the research and development of new products such as digital leadership tools and AI-driven leader assessments. He has published extensively in peer-reviewed journals and was a coauthor of the best article of 2017 published in Personnel Psychology. He is a member of the editorial boards of Leadership Quarterly, Journal of Business and Psychology, and Human Resource Management. John has a PhD in industrial/organizational psychology from North Carolina State University and is a fellow of the Society for Industrial/ Organizational Psychology (SIOP).