Both plant and environmental factors are involved in shaping the methylotroph community on plants. This book is not intended to provide a comprehensive review of metabolism of methylotrophic bacteria. Instead this book focuses on significant recent discoveries that are both refining and transforming the current understanding of methylotrophy as a metabolic phenomenon. The book also examines new directions in methylotroph ecology that improve our understanding of the role of methylotrophy in global biogeochemical processes, including the future challenges in the field perspective.