Europe’s forests have provided human societies with essential ecosystem services and great economic values for centuries. Some of these values are now increasingly threatened by climate change, which greatly intensifies forest disturbances such as bark beetle outbreaks. However, some past management practices have also increased the vulnerability of Europe’s forests. For example, due to its good growth performance and favourable properties for forest industry, Norway spruce has been planted extensively in Europe over the past century, including in areas outside its native range. This has created large areas of so-called secondary forests, which have increasingly exhibited problems with health and vitality and are prone to various disturbances: the most important being wind, drought and bark beetles. This report aims to help European and national policy makers understand the complex roles bark beetles play in our forests, and provide the scientific basis for robust forest policies and management options to address these emerging bark beetle problems.