The Rijksmuseum presents two restored panels which are among the most important Renaissance paintings in the museum's collection, namely the portraits of Giuliano and Francesco da Sangallo by Piero di Cosimo (1462-1521). Giuliano was a prominent Florentine architect, his father Francesco a musician. The two panels are among the earliest portraits to be painted of representatives of an occupational group. The research and restoration process revealed a number of new historical facts surrounding the works of art.Dating from c. 1485, the portraits, which are on long-term loan from the Royal Picture Gallery Mauritshuis in The Hague, have been undergoing extensive restoration since 2004. The restoration also provided an excellent opportunity to study Cosimo’s use of materials and his painting style, as well as to reassess the portraits’ significance in an art- historical context. Particular attention was paid to the question of the extent to which the portraits, which were separately framed, constituted a whole. After the restoration and research had been completed, it was decided to present the works in a single frame.The man on the left is Giuliano da Sangallo (1442/45-1516), the person who commissioned the paintings. The man on the right is his father, Francesco Giamberti (c. 1404-1482) who died before his portrait was painted. Both paintings reveal the profession of the person portrayed. In Giuliano’s case, the pen and pair of compasses in the foreground show that he was an architect, while the sheet of music tells us that his father was a musician. Francesco was employed both as an architect and musician by the Florentine ruler Cosimo de’Medici. His son ended his career as one of the leading architects of St Peter’s Basilica in Rome.The panels remained in the possession of Giuliano’s son until his death in 1576. They were then incorporated into the collection of the British royal family until King William III brought them to the Netherlands for display in the royal residence Het Loo. Since then the works of art have remained in the Netherlands.