A quarter of world’s forests are in mountain areas. These forests typically have high biodiversity, and provide many goods and services for people both in the mountains and the lowlands, often far away. Mountain forests are important as sources of wood, as well as other products such as medical herbs. When managed well, they are also vital for ensuring reliable supplies of high-quality water and for protection against natural hazards such as avalanches, landslides and floods. They are also the setting for tourism and many recreational activities. This publication, a contribution to the International Year of Forests, presents the many values of mountain forests, outlines current challenges for their management, and proposes recommendations for their sustainable management.