While information on the roles and regulation of transporters for all major nutrients and metabolites in plants has increased significantly, a synthesis of this research has been lacking. Based on current research in genomics and proteomics, this book clarifies the identification and characterization of plant membrane and vacuolar transporters. Transporter functions such as mineral nutrition, cell homeostasis, storage and stress responses are examined with a focus on enhancing nutrient use efficiency in crops, and increasing crops' ability to withstand nutrient stresses and improve nutrient storage.