This book is about the regeneration of plants from seed under field conditions. It attempts to give a reasonably balanced overview of the many aspects of this broad topic. The first chapter introduces some general ideas about reproduction in plants. Subsequent chapters deal with the early stages in the life of a plant, from ovule to established seedling, in a more or less chronological order. The final chapter shows how the data on regeneration requirements of different species can be used to explain a number of important characteristics of whole plant communities. The study of the ecological aspects of reproduction by seed touches on a range of issues of current interest in biology. A discussion of seed size and number involves a consideration of the concepts of resource allocation, life cycles and strategies. The in- teractions between plants and animals seen in pollination, seed dispersal and predation provide excellent material for the study of coevolution. Investigations on regeneration from seed have greatly our understanding of the causes and maintenance of species added to diversity. The reader will find that virtually all the experiments and field observations described in this book are conceptually very simple. Many of them merely required numerous careful measurements.