Radiation therapists (RTs) need to engage more in research for the benefit of their patients and their own professional development. However, radiation therapy in Australia is new to research with an undeveloped research culture, so RTs need direction when wishing to embark upon research projects. This manuscript provides the results of the first stage of a Delphi process aimed at defining RTs' areas of research interest. Questionnaires were sent to all Australian departments of radiation oncology (n = 41) asking for a group in each department to identify what problems they experienced while treating patients or working with colleagues, and what areas of radiation therapy they felt required further research by radiation therapists. The response rate was 70.7%. Of the designated RTs who collected the data, 82.8% had greater than 10 years experience and 48.1% had postgraduate qualifications. Two of the researchers categorised the responses and derived a list of themes to describe the identified questions. Of 410 research questions, 374 could be coded (91.2%). The categories defined were “Staff issues” (58.3%), “Technical issues” (28.9%) and “Patient related issues” (12.9%). The RTs were interested in many research areas, but it is of concern that the largest theme identified was “Staff issues”, which could indicate some dissatisfaction in the workplace. However, it was clear that RTs are thinking about their practice and identifying gaps in knowledge in the technical and patient related areas. The second stage of this project was to create research areas that represented the themes identified in this first stage and send them back to the radiation oncology departments for prioritising; these data are currently being analysed.