The monitoring in Swiss forest reserves has been relaunched based on a nationwide consistent concept. It is intended to give federal authorities a basis for policy controlling in the field of forest reserves and to enhance the understanding of forest succession without human intervention. The monitoring encompasses forest structure and tree characteristics which are important as habitats for organisms. It combines surveys on some 95 ha of core areas of 0.1 to 3.3 ha large with an inventory on some 1700 sampling plots, similar to those used in the Swiss National Forest Inventory. The monitoring takes place in 14 forest reserves with intensive observation and in about 30 reserves with extensive observation. The reserves observed by ETH, which have been observed for 20 to 50 years, play an important role in the reserve network. The monitoring will provide information about forest and habitat structures for widespread phyto-sociological communities. This report accounts for the methodological decisions made and for the selection of the forest reserves under observation.