The proliferation of mini-publics as emblematic instruments of a more deliberative democracy relies on the method of sortition. The latter, since Antiquity, supposedly does away with self-selection, and instead guarantees equality, unpredictability, and the impartiality of the selection. Moreover, from the contemporary point of view of deliberative theory, sortition ensures better inclusiveness. Yet this chapter analyzes a specific case in light of the relative literature, showing instead that the process of recruiting a mini-public, generally described as “random selection,” is in fact the selection of individuals who are ultimately volunteers. Moreover, the differences between participants and non-participants are significant enough to influence the dynamics of the deliberation. The process combines an initial random sampling, often non-probability based, with self-selection of participants according to various motivations, their availability for the scheduled dates, and their recruitment carried out in such a way as to ensure the representativeness of the mini-public. Recruitment (of an initially randomly selected group) mobilizes individuals in different ways depending on their motivation to participate in a collective and deliberative exercise, their activity online when they are already members of an online panel, the topic itself, and the conditions of participation (especially remuneration). The mix of random recruitment, motivation, and biographical availability preferentially selects “deliberative citizens” who place more importance than non-participants on expressing their opinion, find more pleasure in participating in collective exercises, are less wary of face-to-face political disagreement, and are more willing to shift their opinions, given the social value they attribute to collective discussion.