Francesc (sometimes "Francisco") Valls was a major figure among Catalan composers of the Baroque and made important contributions to the theoretical thinking of his day. Although his traditionally accepted birth date is placed at 1665, recent studies show that the date was more likely 1671. First mention of Valls in historical accounts comes from 1688 when, in quick succession, he was awarded the duty of overseeing church music in the parish of Mataró, in addition to holding down the post of musical director at the cathedral in Gerona. In 1696, Valls accepted the position of maestro at the cathedral of Saint Maria del Mar in Barcelona; that same year he took over the position of interim maestro at Barcelona Cathedral proper, but was not promoted to the status of a full maestro di capilla until 1709. Although Valls composed his most famous work, the "Missa Scala Arentina" with its distinctive minor ninth in the second soprano part in the "Gloria," in 1702, it took some time for its impact to register among Valls' colleagues. In 1715, Grenada-based composer Gregorio Portero went on the offensive, accusing Valls of "destroying the very essence of music" through his bending of what was then perceived as irrefutable laws of harmonic motion. This began a widespread war of letters and articles among Spanish musicians in a controversy that ultimately spread to Italy. Valls' own final word on the subject was in the treatise "Mapa armonico" (1741-1742), written after his retirement from Barcelona Cathedral, a work that was widely circulated in manuscript form. It is full of valuable information about performance practices of the Spanish Baroque and elsewhere and includes several complete compositions as examples and tips on continuo realization. Valls left an extensive output of works; at least nine masses, nine Magnificats, a set of litanies in six voices, and numerous motets, which usually involve double chorus, continuo, and orchestral parts; unfortunately, none of his oratorios have survived. He also left a sizeable number of villancicos and other popularly oriented pieces. The large amount of music that Valls left combined with the fact that music manuscripts of his works are scattered throughout Spain has hindered its revival outside of the Missa Scala Aretina. From this standpoint at least, things are looking up for Valls, as the first thematic catalog of his music appeared in 1997.