The article presents a brief overview on Italian laws regulating prison libraries and the Agreement, which included in “Biblioteche di Roma” (i.e., the Rome Public Library Network) the libraries of the prisons located in Rome. The paper focuses on the loan service delivered by the prison libraries of the Casa Circondariale di Rebibbia Nuovo Complesso (i.e., Rebibbia Prison - New Complex), the Roman prison that hosts the largest number of inmates, and presents the results from the survey carried out in 2017 (January-July), from which the favorite literature genres by the prison population emerge.