Trees include some of the largest and longest lived organisms on our planet; they have always been a source of food, protection, and sustenance for men and other living beings. Unity is strength, and the real wealth of the planet is not individual trees but forests. They constitute the most evolved formations in many parts of the emerged lands and are among the richest ecosystems on the planet, hosting about 80% of the world's terrestrial animals and plants. This book seeks to reveal the wonders of forest ecosystems by assessing how they work, where they are, and how they look. It consists of 12 chapters which, starting from the definition of tree and forest, present the forest ecosystem at different scales, the mapping of the planet's forest resources, the diversity of forests, how they have changed over millennia, the effects of climate change on forest ecosystems, and their future. The book is completed by a glossary, additional resources, notes on contributors, the index, and picture credits. About 250 beautiful colour photographs, many of which are full pages, impressed me; these alone make the book worth owning. The text is written in a clear, scientific style that also winks at the non-specialist reader. Numerous diagrams and colour graphics make the text clearer and more intuitive. Insiders will also find lots of interesting information. In my case, I could learn more about the Tropical Rain Forest and the Taiga, which are the ecosystems I know the least. I was surprised to learn that Southeast England was covered with tropical forest 50 million years ago! The authors, three American and one European ecologists, have extensive experience in biodiversity inventory supported by the most modern data acquisition and analysis techniques. In these chapters, they present the fruit of their decades of experience in an up-to-date overview of the field. The considerable size of this book, over 2.3 kg, is also its main flaw. It cannot be easily carried around and must be consulted on a table. An ebook version that can be read on tablets exist and is perhaps more useful to researchers, but certainly less fascinating.