Ultraviolet-B radiation (UV-B) has profound effects on plant growth and development, and exposure varies with ozone depletion and across geographic regions, with ecosystem and agricultural consequences. This book deals with large-scale impacts but also how UV-B affects plants at the molecular level is also fascinating, and the UV-B photoreceptor has only recently been characterised. While UV-B radiation can be damaging, it also has a more positive role in plant photomorphogenesis. Consequently UV-B treatments are being developed as innovative approaches to improve horticulture. This book is a timely synthesis of what we know and need to know about UV-B radiation and plants.