Large herbivores are, and have for a long time been, among the major drivers for forming the shape and function of terrestrial ecosystems. These animals may modify primary production, nutrient cycles, soil properties, fire regimes as well as other biota. Some large herbivore species/populations are at the edge of extinction and great effort is being made to save them. Other species/populations are under discussion for reintroduction. Still other species occur in dense populations and cause conflicts with other land use interests. Overall, most large herbivores need some type of management and, according to our view, these operations should be scientifically based.

There is a great amount of scientific information on large herbivores in different regions of the world. We felt that there was an urgent need to bring this knowledge together and to make it available for a larger public outside the group of specialists. We also felt that synthesis of results from one region may be valuable for scientists working in other regions and with other species.

To initiate a first synthesis of the knowledge on large herbivores we held a workshop on ‘The impact of large mammalian herbivores on biodiversity, ecosystem structure and function’ 22–26 May 2002 at Kronlund outside Umeå in northern Sweden. The event brought together scientists from different disciplines and with experience of large herbivore research in different biomes. During the workshop the idea of a book was developed over time and some more specialists were invited to the synthesis.