User involvement is widely promoted within the European healthcare sector as an effective means of developing patient-centred health services. In addition, user involvement is recommended as an important aspect of developing effective cancer services. Despite the acknowledged benefits of user involvement, this concept has not been fully endorsed in Greece. Greek healthcare users may be increasingly involved in the decisions made for their health, but their involvement in cancer services planning remains very limited. The aim of this study was to identify healthcare users' key areas of cancer care and services that needed to be developed or improved in Greece and prioritise them through a consensus building study. A Delphi technique was used to collect data from a sample of 30 healthcare users in two rounds. The response rate for each round was over 80%. The main consensual issues prioritised by the healthcare users were the improvement of education for health professionals and the development of effective treatments. Other areas that were also rated highly included the organisation of cancer services, the need for more resources and improvements in the attitude of healthcare professionals. Healthcare users' priorities were focused on timely diagnosis and treatment by well-educated healthcare professionals, demonstrating a strong will for survival. Based on the findings from this study and the literature recommendations, it is expected that the re-organisation and fair distribution of the existing resources could improve the experience of healthcare users. In addition, the number of employed nurses should increase and improvements in healthcare professionals' education should be implemented in order to develop and improve cancer services. Public health education needs to be emphasised and prioritised especially in areas such as prevention and screening. The Greek government needs to address and encourage user involvement in planning healthcare services with the introduction of relevant legislation.