We have tried to make this book lively and practical, minimizing the lists of labels, levels, and categories that are likely to be forgotten before the final exam is graded. Instead, we emphasize basic research findings and the ways they apply to children, parents, and the adults who work with both. The book is organized chronologically, from conception, heredity, birth, and infancy, through early childhood, middle childhood, and adolescence. For each stage, physical and cognitive development and social and emotional development are discussed in separate chapters, but always, we point to the interplay between these topics.