In addition to composing and performing his own work, Horta has worked for many years as arranger or sideman for Brazilian artists such as Elis Regina, Milton Nascimento, Maria Bethânia, João Bosco, Airto Moreira, Edu Lobo, Nana Caymmi, Flora Purim, Gal Costa, Sérgio Mendes, Chico Buarque, Flávio Venturini, Joyce, Johnny Alf, Wagner Tiso, Francis Hime, and Beto Guedes.
