Abstract: The article offers a brief overview of the projects developed by the Hispanic Seminary of Medieval Studies since the publication of Kasten's article in 1978, where he briefly explains the decision to abandon the compilation of the paper-based Tentative-2, in favor of a computer based lexical database, and the origins of the Dictionary of the Old Spanish project. The article pays particular attention to two projects related to the paleographical transcriptions produced by HSMS's collaborators: the Digital Library of Old Spanish Texts, which provides interactive access to a the paleographic transcriptions, as well as to a series of indexes (alphabetical, frequency, reverse alphabetical), and concordances in KWIC format; and the Old Spanish Textual Archive, a lemmatized and morphologically tagged linguistic corpus of about 35,000,000 words of medieval texts written in Spanish, Asturian, Leonese, Navarro-Aragonese, and Aragonese.