The Series 20/21 programme, organised by the National Centre for Music Dissemination (CNDM), comprises 24 concerts dedicated to music from the last century and to contemporary creations.

The settings are the National Auditorium and Auditorium 400 in the Reina Sofía National Art Museum. The former will hold the series on 20th century music, played by some of the most important international soloists and ensembles. The latter will hold more recent music, especially by Spanish ensembles. Each programme is divided into series (Tributes, Degenerated music and Bartók première) or unique programmes such as First-time (Auditorium 400), and Frontiers and Perspectives (National Auditorium).

Some of the guest ensembles include Sax-Ensemble, Grupo Cosmos21, Grupo Enigma, la Camerata del Prado, Trío Arbós and bcn216. Some of the soloists that are worth mentioning include violinists Viktoria Mullova and Daniel Hope, German composer Jörg Widmann, guitarist Gabriel Estarellas, the doyenne of Russian pianists Elisabeth Leonskaja and the young French pianist Bertrand Chamayou.