Since the second half of the twentieth century, the punitive trend in our societies has led to prison overcrowding. In France, as of January 1, 2020, there were 70,651 inmates in prison for an accommodation capacity of 61,080. Public opinion, which is aware of this issue, and the media obsessed by street crime are exerting political pressure to devise ways of preventing young people from entering a career of delinquency and of reducing high rates of reoffending : three years after release, 2 out of 3 ex-prisoners return to prison.After the development of several sentence adjustments and alternative measures to prison — parole, probation, community service, and more recently, electronic monitoring — probation has had to face a great deal of criticism and develop new insights to respond to its detractors by empirically justifying its contributions. This is even more the case with the rise of rational choice theories to explain crime — highly critical of the role of prevention and probation — whose transcription into public policy in the form of systemic penal hardening has led to an increase in incarceration and reoffending rates.In response, research on desistance has emerged in the United States and has shown that the vast majority of people involved in offending eventually get out of it, often through pathways that stray from the perimeter of institutional actors' interventions, or sad to say, seek to escape their counterproductive effects. Studying the mechanisms that govern the process of desisting from crime in France is thus at the heart of this thesis. The approach presents the originality of collecting the experience of individuals in order to understand the course of desistance and thus completes insights into the effects on and reception by its public of penal policies.In the course of this research, allowed for by the opening of the probation services and those of the city of Paris, 33 tales of desistance were collected on the Parisian territory, using the biographical interview method. The inductive analysis of this qualitative material produced new knowledge on the pathways out of crime. Thus, this work has highlighted at least 3 major forces that are articulated in this process :•The influence of spheres of socialization which evolve, express themselves and/or fade in the reorganization of a path outside a former deviant referential.•The various stigmas and blocking representations to be deconstructed in order to bring about this change: about offenders ; about the money they yielded ; about the opportunities offered or denied by passing the “crime” square.•The key role of resource persons in such trajectories, which allowed to propose a typology of the trajectories of desistance according to their basic endowment of resources, their relationship to institutions and the progress in the constitution of new capitals to initiate and accomplish their conversion.This research is an encouragement to multiply the entry points for understanding the complex process of exits, including the viewpoint of the desisters. It aims to establish the basis for a longitudinal and systematized study of the future of those who withdraw to increase their chances of success and hasten the onset of their commitment to an exit.