Introduction: The experiential knowledge of patients can provide research communities with complementary perspectives on disease. The aim of this study was to identify and prioritise everyday problems and research needs of haematological cancer patients and people who have undergone a stem cell transplantation. Methods: A mixed-method participatory research approach (the Dialogue Model) was applied, including interviews (n = 19), four focus group discussions (n = 27), a questionnaire (n = 146) and a stakeholder dialogue meeting (n = 30) with patients in the Netherlands. Results: Patients’ physical discomfort, psychosocial issues, problems with the healthcare system and policy issues were highlighted. Respondents prioritise research aimed at factors potentially influencing survival, such as lifestyle, and research aimed at improving patients’ quality of life, for example improving memory and concentration problems. Topics also focused on physical discomfort, causal mechanisms, and healthcare organisation and policies. Research of a social scientific character is underrepresented, and as such, patients’ everyday problems are not all directly reflected in the research agenda. Conclusions: Our findings indicate that patients, besides emphasising the importance of improving survival, have a clear desire to increase control over their lives.