The attempt to halt the remorseless spread of organised crime in the Italian South should not just be an issue for the judges, investigating magistrates and forces of order; every citizen should feel that they are an integral part of a wind of change, coming from below, that can have a decisive impact on local society. Starting from this premise, art and culture, adopting an approach of participation and involvement, can play a primary role in processes of renewal. In various areas within the provinces of Naples and Caserta, carefully researched works of street art, with the direct involvement of the local population, have provided the means for intervention in decaying and marginal environments where organised crime seemed to be so well entrenched as to be ineradicable. This article presents four case studies, analysing their assumptions, methodology and objectives.