Radiation therapy is one of the core components of multidisciplinary cancer care. Although similar to 50% of all European cancer patients have an indication for radiotherapy at least once in the course of their disease, more than one out of four cancer patients in Europe do not receive the radiotherapy they need. There are multiple reasons for this underutilisation, with limited availability of the necessary resources - in terms of both trained personnel and equipment - being a major underlying cause of suboptimal access to radiotherapy. Moreover, large variations across European countries are observed, not only in available radiotherapy equipment and personnel per inhabitant or per cancer patient requiring radiotherapy, but also in workload. This variation is in part determined by the country's gross national income. Radiation therapy and technology are advancing quickly; hence, recommendations supporting resource planning and investment should reflect this dynamic environment and account for evolving treatment complexity and fractionation schedules. The forecasted increase in cancer incidence, the rapid introduction of innovative cancer treatments and the more active involvement of patients in the healthcare discussion are all factors that should be taken under consideration. In this continuously changing oncology landscape, reliable data on the actual provision and use of radiotherapy, the optimal evidence-based demand and the future needs are crucial to inform cancer care planning and address and overcome the current inequalities in access to radiotherapy in Europe.