The scientific activity of Maddalena Modesti focuses on various lines of research related to each other, concerning both latin Palaeography and Diplomatics.
In the field of latin Palaeography, she is interested in the study of documentary scripts of the IXth century of North Italy, reconnected to the critical edition of the charters, and also with the Bolognese manuscript production of the XI-XII cent.. Her research interests extend beyond the study of the activities of the scriptorium and the library of the monastery of S. Silvestro of Nonantola (VIII-XI cent.) and that of reused fragments of manuscripts, i.e. with the discovery of an ancient and venerable fragment goto-Latin palimpsest of the De Civitate Dei Augustine (VII cent.). She is interested also in the study of 'mercantesca' and that of legal manuscripts, and more generally in the relationship between writing and law.
In the field of Diplomatics, a common thread is represented by the early medieval documentation of north-central Italy, with the edition for the series of Chartae Latinae Antiquiores of ninth-century documents preserved in Modena, Nonantola, Arezzo, Florence, Reggio Emilia, Milan and Bergamo. Another central theme is represented by medieval Bolognese notary (XII-XV cent.), with the project of critical edition of the XII century Bolognese charters. Her research activity is also addressed to the medieval cartularies, with the study and the critical edition of the oldest Bolognese documentary collections (XII-XIIIin.) and with the census of ecclesiastical cartularies of Emilia Romagna, as part of the Interantional Research Project 'Les cartulaires ecclésiastiques de l'Italie médiévale' promoted by the École française de Rome