In this article I use Foucault's theory of power to explain children's presence on the streets. I argue that resistance to be subject of family power and to be subject of the power exercised in shelters or governmental institutions is not the only struggle in which participates a child that decides to stay living on the streets. Subsistence is difficult; resources are scare. Children need power to survive, to protect themselves, to stay. Therefore, permanence cannot take place without a minimum amount of power. I find that, when children are on the streets and are given an option, they establish a balance between the street and previous experiences outside the streets. But, not all children have an option or the possibility of exercising that option. My main aim is to understand the reasons why a child stays living on the streets even when she has to face situations as problematic as the situations confronted while living in their home or in a shelter Keywords: Street children, adolescents, power relations, resistance, Foucault.