"Deliberative turning point," "participatory imperative": today, many citizens, decision-makers, and researchers see participation as a way to deepen and revitalize the democratic process.

However, concrete mechanisms aimed at involving stakeholders with competing interests in the same process (of knowledge or decision-making) still largely remain experimental. What determines the success or failure of a participatory experience? By what criteria should it be evaluated? How can mechanisms be designed to "hold"?

More than a defense of the merits of participation, this work puts it to the test through a series of feedback from experiences. Focusing, on one hand, on the exploration of controversies and, on the other, on the evaluation of public policies, the chapters describe the methodological challenges researchers faced in integrating diverse publics into the decision-making process and bringing forth representations essential to understanding political and social phenomena.

The book thus invites a better understanding of this exciting but uncertain participatory adventure, through approaches by researchers sharing a common experience and methodological culture.