This is a theoretical paper, which presents a systematic and critical review of different authors about the neighborhood effect and the State's role in the life paths of young people and introduces reflections, contributions and nuances that have emerged from an empirical work, with the intention of advancing the conceptual reflection of phenomena such as neighborhood effect and processes of youth social exclusion on the outskirts of the city. The methodology chosen is the comparative case study among four working class neighborhoods in the periphery of Barcelona and Milan. Finally, main conclusions are: previous researches about neighbourhood effect have ascribed other elements to the neighbourhood leading to social exclusion, even when they are not created by neighbourhood itself, but they are the result of extra-territorial and extra-local processes.