Suserup Skov in Denmark is a well-preserved beech-dominated forest reserve with continuity in tree cover at least back to 4200 BC, indicating it to be a direct descendent of the primeval forests. Despite of documented historical impact from humans, Suserup Skov is now increasingly characterized by natural disturbance dynamics and is one of the best reference areas for naturalness in the nemoral part of northern Europe. This has attracted several research projects focussing on forest dynamics, ecology and biodiversity which are summarized in this issue of Ecological Bulletins. This volume focuses on three main areas: 1) stand structures and dynamics 2) water and nutrient cycling processes, and 3) vegetation patterns and processes. With a compilation of scientific reviews, detailed case-studies and experimental works, the volume provides a unique and in-depth overview of structures and processes in a single forest reserve. The aim is to establish a basic reference of science and practice within forestry and nature conservation.