BackgroundAlthough radiotherapy is required by more than half of cancer patients, access to radiotherapy remains far from optimal. At least one in four European cancer patients do not receive the radiotherapy they require, and the uptake of innovations in radiation oncology (RO) is often slow and haphazard.Value-based approaches can help bridge these gaps in radiotherapy, especially by facilitating the assessment of new interventions. However, current value-based frameworks in oncology do not sufficiently consider RO specific aspects. For example, the diversity of innovations (from masks to proton beam therapy to AI) that need assessment; the upfront resources or workforces required to support implementation; or the need for non-traditional endpoints to capture adequately the benefits of RO, e.g. organ preservation. MethodsThe Health Economics in Radiation Oncology programme of the European Society for Radiotherapy and Oncology (ESTRO-HERO) has proposed to build a robust value-based framework, specifically for RO interventions, starting a three year project as of October 2021. Literature review, qualitative research and stakeholder consensus building through a Delphi consensus approach will be the main methods used in this project. Exploration and consensus building will be undertaken on questions regarding innovative interventions, outcomes, and evidence required for a certain level of benefit. ResultsA three year project started in October 2021, with the first work package tackling the diversity of innovations in RO interventions. A systematic literature review identified twenty-five papers, providing definitions or classifications of innovations in RO. The ESTRO-HERO group will assess the suitability of these in a value-based context, and propose additional aspects if necessary. Future steps are defining and categorizing suitable outcomes for RO interventions, with an important role for patient representatives as crucial stakeholders. To decide the required magnitude of benefit and level of evidence will link the previous steps, and ultimately allow to build a value-based framework for radiotherapy innovations. ConclusionsBuilding a value-based framework for RO interventions will provide a necessary tool for both clinicians and health policy makers, and provide essential evidence for decision making on a local, national and international scale.