Research in radiation therapy is developing as radiation therapists recognise the need for improved evidence-based practice and patient care. However, many radiation therapists have a limited background in the area of research practices and the methodology that may be utilised to answer specific research questions. The purpose of this paper is to describe the development of a research question and the steps involved in determining an appropriate methodology that can be used to answer that research question. To demonstrate application of the approaches and methodologies that are described, an example research question that focuses on the experience of treatment decision-making for early stage breast cancer is considered and referred to throughout the paper. Initially, quantitative and qualitative research paradigms are considered and described to demonstrate the approaches that can be used, the type of data that can be collected and the results that can be analysed and utilised to answer the research question. As a phenomenological approach was found to be appropriate to investigate the question, this approach is explored in greater detail.