Bark and ambrosia beetle species (Coleoptera: Scolytinae and Platypodinae) have attracted a lot of attention in the past decades following numerous introductions worldwide, many being in relation to international trade. In some cases, massive damage has been noted. Following recent introductions into the EPPO region of new non-indigenous species of bark and ambrosia beetles, concerns were expressed about the risks posed with trade of non-coniferous wood. It was considered that, unlike for conifer wood, the current regulations in place in many EPPO member countries are not appropriate to limit such risk. The EPPO Study on the risk of bark and ambrosia beetles associated with imported non-coniferous wood was carried out in 2018-2019. This Study was conducted by an Expert Working Group (EWG) including experts on ambrosia and bark beetles, experts on pest risk analysis and risk managers. The objective of the Study was to highlight factors that are important in relation to the potential risks of successful entry, establishment, spread and impact of bark and ambrosia beetles. Biological and other risk factors were identified and were illustrated with examples from 26 bark and ambrosia beetle species or groups of species known to be invasive or posing a threat to plant health. These representative species are classified into three categories based on known damage and level of uncertainty. Based on the information assembled and consideration of the risk factors, horizontal phytosanitary measures are proposed for wood commodities, irrespective of the host plant species and the origin, i.e. for all genera of non-coniferous woody plants and from all origins. The rationale for such recommendation is provided. The study includes case studies and pest information sheets for the 26 representative species or groups of species selected by the EWG. Finally, in addition to the evaluation of the risk factors, information is also provided on non-coniferous woody plants in the EPPO region, as well as non-coniferous wood commodities and trade of such commodities.