"Urban Forests and Trees" is a comprehensive specialist book that results from over six years of intensive collaboration among experts in urban forests and trees from across Europe. The publication brings together insights from 59 authors from 21 European countries and offers a valuable collection of knowledge and research findings in the field of urban forestry. The editors thank the national experts of the COST Action E12 as well as the numerous contributors who have contributed to the various chapters. This book serves as a first European reference on urban forests and trees and is the result of an active community of professionals supported by the COST initiative. The careful editorial support and collaboration with various institutions have contributed to the completeness and quality of this publication.