The UN Convention on the rights of Persons with disabilities provides an example of a Hybrid Forum in which the experience and expertise of stakeholders have been taken into account. Article 12 and its interpretation by representatives of persons with disabilities and activists, which question the legitimacy and legality of legal protection measures, is particularly emblematic in this regard. Taking note of the absence of debates in France on this matter and little visibility of this Convention, a group of researchers in social sciences and humanities—the Collectif Contrast—decided to promote dialogue on article 12 and measures of legal protection and to involve stakeholders. The organization of the first conference in which they sought to bring together researchers, professionals and users, was an opportunity to see the difficulty of involving stakeholders on an equal basis. This led a part of the group to question both the limits and the conditions of participation of persons with disabilities, and to organise another conference and a research programme—the Capdroits programme—seeking to create the conditions for their participation and to put all actors on an equal footing. This article provides an account of these initiatives and then a more general discussion on the participation of persons with disabilities.