The National Library of Spain (NLS, Biblioteca Nacional de España [BNE]) for the target audience of digital humanities (DH), within the last two decades, has taken up major challenges to be into line with other main national libraries (France, The Netherlands, United Kingdom, Germany, and the Library of Congress). The chapter presents NLS's success in the emerging digital scholarship and BNElab Digital Humanities (DH) projects and digital editions (e.g., the Leonardo da Vinci Madrid I & II Codices or Quixote), demonstrating the most necessary steps of libraries to take in the digital age, especially when DH is forming the mainstream and obtaining momentum. The importance of the NLS and its patrimony is in line with its commendatory policy of collaborating with a wide variety of DH projects, and with that of making its digital patrimony freely available. Through a case study of the opening up of cultural heritage data for the arts and humanities (A&H), NLS is challenged from its Semantic Web vision to find the expertise required by the key issues of contemporary digital humanities.