Patient involvement in scientific advisory processes could lead to more societally relevant advice. This article describes a case study wherein the Health Council of the Netherlands involved patient groups in an advisory process with a predefined focus: setting a research agenda for medical products development. A four-phase approach was developed to stimulate needs-articulation concerning future medical products for a broad range of patient groups covering 15 disease domains. 119 (expert) patients and 92 non-patient representatives were consulted using interviews and focus groups. In a facilitated way, patients appeared capable and willing to provide input useful for an advisory process. A broad range of medical products was defined serving different purposes. This study showed two dilemmas: first, finding a balance between a predefined focus and being sufficiently broad to enable patients and patient representatives to contribute, and second, finding a balance between relevance for many patients groups and saturation of data for a lower number of patient groups. By taking the context of patients' daily life as starting point patient groups provided new insights. The predefined focus was sometimes perceived as constraining. The GR considered the articulated needs constructive and incorporated patients' input in their advice to the Minister of Health. © 2012 Elsevier Ireland Ltd.