This contribution has two aims. First to briefly describe the cultural and legislative context produced in Italy by the ratification of the United Nations Convention on the Rights of the Child. Second to present some of the outcomes of the Childrenís city project. This project was started in 1991 and today it involves 46 cities in Italy, several in Argentina and a few in Spain. It is aimed at improving the urban environment from the perspective of children. The study of actions carried out by the Italian cities in order to promote childrenís participation and childrenís autonomous mobility highlights the positive and negative aspects of the project. The main limits of the project are connected with the following factors: project's dependence on temporary tasks of politicians; the emphasis given to the educational dimension of interventions which shifts attention away from the cityís transformation and from childrenís empowerment; the experimental character of the interventions which results in a reduced impact on the urban environment and on the child population. The main positive aspects of the project are related to changes in the perception of childhood, which motivate administrators to make innovative choices and encourages the engagement of larger components of the community.