Everyone who works with forests must measure them, foresters, forestry students, scientists or forest owners. This book summarises modern forest measurement techniques for all those people. It describes how to measure forests, why they are measured and the basis of the science behind the measurements. Trees and forests are large and complex, but even something as difficult as the amount of wood they contain can be measured with quite unsophisticated equipment. This is a book written for all, from professional foresters to the lay person, in fact anyone who needs to measure forests anywhere in the world.