MRD detection is gaining considerable interest as a post-treatment outcome predictor in blood cancers. In Follicular and Mantle Cell Lymphoma its role is clearly established and real time quantitative PCR (RQ-PCR) is the golden standard. However several limitations still preclude a broad application of MRD in clinical practice. These are: i) lack of suitable marker in many patients; ii) presence of false negatives despite very high sensitivity; iii) lack of effective modelization of MRD results. We developed a comprehensive proposal to address these yet unresolved issues, that include both discovery and validation steps. Strengths of the project are a multi-disciplinary research team, availability of clinical databases from several multicenter trials from Fondazione Italiana Linfomi (and possibly other sponsors), presence of MRD results already assessed by RQ-PCR and tissue leftovers (peripheral blood, bone marrow and cell-free DNA) for further lab discovery