This dissertation examines the production, use and preservation of medieval charters and cartularies with regard to what we can know about women's economic activities in twelfth- and thirteenth-century Picardy, France. Charters (medieval records of property transactions) and cartularies (medieval books compiled of charter copies) from three religious institutions located in southern Picardy provide evidence for the case studies examined here. Each institution retains a surviving partial archives of loose charters, as well as a thirteenth-century cartulary. The comparison of their contents enables the creation of two separate sets of charters for each institution—the charters that have been copied into the cartulary and those that have not. This study's findings indicate that those charters absent from the cartulary provide important information about the cartulary charters, particularly regarding women's identities, networks, and activities. Placing the archives charters alongside the cartulary charters offers an opportuntity to reunite and examine multiple charters that focus on either a single transaction, a single woman, a single family or a single charter issuer. In this way, unidentified women in the cartulary can often be linked to natal and marital families, revealing networks of women's activities. Moreover, evidence for non-noble women's participation in economic transactions emerges alongside that of their better-known noble counterparts. This dissertation argues for a broader scope of women's participation in the alienation and acquisition of property in southern Picardy and calls for more research into charter production and its implications for the study of medieval women.