working at Estúdio de Projectos Gráficos, which operated until 1964, de Castro focused on graphic design as well as object design. In 1954 de Castro was a founding member of the Brazilian musical group "Ars Nova." Under the direction of Diogo Pacheco Ars Nova focused on circulating obscure medieval and contemporary musical compositions. De Castro sang baritone and acted as the graphic designer for the group. During this time de Castro began creating concrete poetry and in 1955 published a book of his concrete poems. De Castro was designer and director of the Brazilian theater magazine "Teatro brasileiro." De Castro curated several group exhibitions and solo exhibitions including a retrospective of Aldo Bonadei's work at the São Paulo Museum of Modern Art in 1955. De Castro was honored in 1957 by the Associação Paulista de Críticos de Arte for his scenography and costume design work at the Artistic Culture Theater. Upon his return from studying in Europe for one year (1958–1959), de Castro joined the Neo-Concrete Movement in Rio de Janeiro along with Lygia Clark, Hélio Oiticica, Franz Weissmann, Lygia Pape and others. The following year de Castro participated in "Konkrete Kunst" an exhibit organized in Zurich by Max Bill. From 1959 to 1962, de Castro developed his "Active object" series. In 1963 together with Hércules Barsotti, Lothar Charoux, Waldemar Cordeiro, Luiz Sacilotto among others, De Castro became one of the founders of the São Paulo based art gallery Associação de Artes Visuais Novas Tendências which operated until 1965. Associação de Artes Visuais Novas Tendências was founded and managed by artists working within the Concrete and Neo-Concrete movements but did not solely feature Concrete and Neo-Concrete art. The galleries goal was to provide a space and platform for contemporary art to be presented outside the confines of any particular artistic movement. De Castro is also noted for his series of works titled "Pluriobjetos" which he began in 1970. De Castro's "Pluriobjetos" were first exhibited in 1983 at Gabinete de Artes Gráficas Raquel Arnaud Babenco in São Paulo. Selected exhibitions Solo exhibitions 1983: Gabinete de Arte Raquel Arnaud Babenco (São Paulo, Brazil) 1988: "Aventuras da ordem: Hércules Barsotti e Willys de Castro," Gabinete de Arte Raquel Arnaud Babenco (São Paulo, Brazil) 1994: Obras de 1954 – 1961, Galeria Silvio Nery (São Paulo, Brazil) 2000: "Mira Schendel, Sergio Camargo, Willys de Castro," Centro Cultural Banco do Brasil (Rio de Janeiro, Brazil) 2006: