Background Trade liberalisation and rapid globalisation has led to the increased spread of invasive alien species (IAS) around the world. IAS (plants, animals, fungi or micro-organisms species) are recognised as one of the greatest threats to biological diversity inflicting irreversible damage to the ecosystems they invade. There are an estimated 12 000 alien species present within Europe of which 10-15 % are considered invasive. These species cost the EU around €12 billion per year. To mitigate the on-going threats of IAS to the EU, the European Commission adopted the EU Regulation (No. 1143/2014) on the prevention and management of the introduction and spread of IAS. The Regulation, which came into force on 1 January 2015, aims to address the negative impact IAS have on biodiversity, ecosystem services, human health and the economy in EU Member States. The Regulation is centred on three main themes: prevention; early warning and rapid response; and management. It will restrict the use, trade and transport of IAS listed of EU concern. When initiating the programme on Invasive Alien Plants (IAPs) in 2002, EPPO and the IAP panel assembled a preliminary list of 500 IAPs in the EPPO region from scientific and technical documents. A preliminary prioritisation of these species was made on the following considerations: whether the species is considered invasive or potentially invasive within the EPPO region; whether the species is absent or containable by appropriate means; the potential of the species for further spread and damage into significant areas where it is absent; and whether the species is reported to be spreading or becoming more damaging in its current distribution. In 2012, EPPO and the IAS panel developed the EPPO Prioritisation Process for IAPs where species are assessed to determine whether they should be included in the EPPO Observation List of IAPs (species that present a medium risk to the EPPO region) or the EPPO List of IAPs (species that present a high risk to the EPPO region). Species included in the EPPO List of IAPs are further assessed to determine if they are a high, medium or low priority for a pest risk analysis (PRAs). Currently, the EPPO List of IAPs contains 15 species that have a high priority for a PRA. When designed in 2012, the EPPO Prioritisation Process was originally developed based on the International Plant Protection Convention (IPPC) requirements. The current LIFE Preparatory call “Developing risk assessments on Invasive Alien Plant species” known simply as (IAP-RISK), aims to address IAPs – one of the largest groups of IAS in terms of number of individual species and the area they occupy. When invading a habitat, IAPs can outcompete native flora, degrade and alter ecosystem services, deplete biodiversity, cause negative impact on human health and require costly control and management programmes. Objectives The overall objective of the IAP-RISK project is to mitigate the threat of IAPs to the EU by producing high-quality PRAs that meet the requirements of the EU Regulation (No. 1143/2014) and the minimum standards set out in the horizon scanning exercise ENV. B./ETU/2013/0026. Other specific objectives are to: Determine which species from the EPPO List of IAPs and scanning exercise have the highest priority for a risk assessment; Update the Express Decision Support Scheme (Express DSS) within CAPRA (computer assisted pest risk analysis) to meet the requirements of the Regulation and the minimum standards listed in the framework for the identification of IAS of EU concern; and Assess the risk of 16 IAPs by performing PRA that is fully compliant with the Regulation. A secondary objective is to facilitate knowledge transfer and capacity building in pest risk analysis within the EU. The project will disseminate PRAs via its website in two formats (full PRAs and detailed datasheets). Full PRAs will be aimed at the scientific and regulatory community and detailed datasheets will target a wider audience including land-managers, conservationists and researchers. Two training workshops aimed at regulators, scientists, land-managers and other interested stakeholders will build capacity within Europe in species prioritisation and PRA. Expected results: The IAPs-RISK results will include the following: A risk-based list of 37 IAPs that identifies 16 top priority species for a PRA; An updated version of the ‘prioritisation process’; An updated version of the Express DSS housed within the CAPRA software specifically for IAPs; 16 species specific risk maps detailing the current and potential occurrence of 16 IAPs; An R code (statistical software code) to implement model workflow in future risk assessments; 16 draft PRAs; Eight expert working groups where each group risk assesses two IAPs; 16 fully peer reviewed PRAs; Two training workshops on the EPPO prioritisation process and EPPO Express DSS, each attracting at least 20 participants; Eight LIFE or non-LIFE projects/networks engaged; A project website with 2 500 visits per month (English with French summary); Eight quarterly reports in the EPPO reporting service reaching more than 3 500 stakeholders per report (English and French); Four biannual electronic newsletters reaching 2 500 stakeholders per newsletter (English and French); A poster ‘selection of 16 species for PRAs’ disseminated to more than 500 stakeholders; 16 species specific posters/leaflets on the output of the PRA disseminated to more than 500 stakeholders; 16 species specific datasheets published in the EPPO Bulletin with 700 downloads per datasheet; A report on selecting 16 species for PRA and a report detailing the species distribution modelling; A socio-economic report included within final report; and 16 IAPs potentially recommended for regulation by the EPPO Council and regulated by the European Commission as species of EU concern.