The purpose of this textbook is to present classical plant development in modern, molecular-genetic terms. The study of plant development is rapidly changing as genome sequencing projects uncover a multitude of new genes. This book provides a framework for integrating gene discovery and genome analysis into the context of plant development. Taking a systems approach, concepts in plant development are compared to those in animal development, and complex processes, such as flowering and photomorphogenesis, are presented as pathways of gene action regulated by positional and environmental cues. The author places emphasis on organ formation, such as the development of roots, shoots and leaves; and life cycle events such as embryogenesis, seedling development, and the transition to flowering. The book takes examples primarily from model plants with well-studied genetic systems, particularly Arabidopsis and maize. Molecular Genetics of Plant Development is designed to be used as a textbook for upper division or graduate courses in plant development.