This work is the accomplishment of an action-research carried out by a professional in the field. As a specialized educator and project manager in a service specialized in prostitution in the Paris region, I have put to good use eight years of listening to the life stories of young people. Indeed, this integration and prevention service completes its educational action with the tools of life history and genogram practice. My practice has allowed me to understand the problem of the risk of prostitution in the light of what they say and their reality. Today, in a difficult life context for young people between 18 and 25 years old, who have lost their family and social ties, the approach to the risk of prostitution and prostitution has changed. Their extreme risk-taking practices are invisible and unnamed and very often escape the institutions that accompany them. The act takes precedence over the word. The theme of my research is to analyze and better understand how the biographical device can reduce risk-taking among young people, and to identify the different factors of the slide into prostitution on which it is possible to act.