This introduction presents an overview of the key concepts discussed in the subsequent chapters of this book. The book discusses six broad ideas regarding context, principles, and themes, and highlights some of the limitations of athletic development research. It outlines research insights and factors that contribute to the ecology of athletic development environments. The book argues that the capacity for athletes to adapt to change and to cope with adversity is fundamental for their progress. It explores how closely athletic development and learning are intertwined. The book argues that if more people in sport viewed athletes as ‘learners’, coaches as ‘learning facilitators’, and the places they inhabit as ‘learning environments’, then the culture and focus of sport would be more likely to be effective developmentally. It presents part of the picture not the holistic whole.