There are collectors keen to amass trophy pieces – and then there is Pedro Barbosa. Over the years, the former trader has gathered one of the most significant collections of conceptual art in South America, relentlessly challenging his own understanding of what art can or should be. Among the highlights are pieces by Hans Haacke, Robert Barry, Stanley Brouwn, and Cildo Meireles to name just a few. Artworks, though, are only one part of Barbosa’s scholarly interest. The collector is also a keen archivist, collecting everything from avant-garde magazines to invitation flyers, rare posters, and records that he keeps carefully filed in the basement of his São Paulo home. Such is the depth and richness of Barbosa’s archive that museum directors and researchers from around the world have made it an essential stop on their Brazilian tour. In this exclusive interview, Barbosa gives a private tour of his holdings, which wouldn’t be out of place in a world-leading institution.