Hespèrion XXI is an international early music ensemble. The group was formed in Basel, Switzerland in 1974 as Hespèrion XX by Catalan musical director Jordi Savall, his wife Montserrat Figueras, Lorenzo Alpert, and Hopkinson Smith. The group changed its name to Hespèrion XXI at the beginning of the 21st century. The name "Hespèrion" is derived from a word in Classical Greek which referred to the people of the Italian and Iberian peninsulas.
The ensemble is noted for its scholarship in early music, especially the music of 16th and 17th century of Spain. Their performance practice is noted for the liberal use of improvisation around the basic melodic and rhythmic structures of the early pieces, resulting in great emotional intimacy and immediacy.