The citizen forum method was used during a study carried out in Romansh-speaking Switzerland to gather opinions – hopes and fears – about advances in genomic medicine in oncology. The intention was to encourage dialogue and mutual learning between specialists – in genetics, oncology, sociology, anthropology and ethics – and members of civil society. The aim of this article is to analyze the organization of discussion groups using deliberative exercises that favoured exchanges of opinion, as well as the citizen public’s experience of these forums. The analysis results highlighted the advantages and limits of the forum method. The exchanges were characterized by high points often based on personal experience and sparked by different points of view, as well as the horizontal nature of discussions between citizens, and given value by the attentive way in which the experts listened. Participants were engaged in a process of critical reflection, both personally and collectively, sometimes extended by discussions with those around them that multiplied the number of exchanges. However, the difficulty of adapting the suggested activities to the varied levels of knowledge of the field of genomic medicine came through, as did the fact that the research team “wore two hats” as both experts and moderators.