PURPOSE: Health technology assessment (HTA) involves trade-offs between benefits, risks and costs. Most countries require evidence on these outcomes, but decision making also requires value judgments on the relative importance of the potential benefits and harms of the drug. When making such judgements, decision makers can make use of evidence on the preferences of patients, experts and the general population. At present, there is no overview of the use of preference research in European regulatory decisions. The ISPOR Stated Preference Special Interest Group undertook a systematic literature review, a review of regulatory guidance documents and a search of official websites to ascertain whether and how stakeholder preferences are included in regulatory decisions. European HTA bodies were then surveyed to confirm and elaborate on their use of preference data. This workshop summarizes the results of this project, by presenting an overview of methods that are currently being used or considered, and shows how several initiatives are intended to further develop the use of preference data. DESCRIPTION: Axel Mühlbacher will provide an overview of the ISPOR working group project, including the typology of decisions and methods. Kevin Marsh and Janine van Til will summarize the current use of preference data, the results of the systematic literature, and the survey. They will discuss which of the 31 European countries are currently using quantitative preference data, and the methods accepted. Case studies will illustrate the methods identified, including: the use of patient preferences to generate aggregate benefit functions in Germany; the use of MCDA to support reimbursement in Italy; and the use of general population preferences to estimate utility tariffs in the UK. Axel Mühlbacher will conclude the presentations by summarizing ongoing initiatives that will inform the future use of preference data.