17th and 18th century inventories of the Spanish royal collection record numerous works by Rubens. Among the painters who visited Spain long enough to leave their mark, Rubens was the greatest and the one whose infl uence lasted longest. His artistic background, erudition, trips to Italy, travels as a diplomat and peace negotiator, professional and personal success and discerning appreciation of all the arts (evident in the drawing by Martin van Heemskerck, which Rubens enlivened with his own strokes) make him a truly exceptional man and artist. Visiting Rome in 1600 Rubens admired the classical world, refl ected in his Birth of Apollo and Diana and The Seven Sages of Greece. He also assimilated the innovations of Italian and foreign artists, including Elsheimer with his landscapes and nocturnal scenes. Generous with his knowledge and fame, Rubens supported his pupils such as Van Dyck and encouraged the young Velázquez in his desire to go to Italy. His understanding of the nature of artistic collaboration and its potential gave rise to works such as The Virgin and Child in a Painting surrounded by Fruit and Flowers and the series on The Senses, for which Jan Brueghel the Elder executed the landscapes, fl owers and animals. The preparatory oil sketch, in which Rubens was peerless, provided him with the optimum format for expressing his masterly command of a rapid, deft brushstroke, exquisite colour and ability to convey dynamic movement. Examples on display here include his studies for the paintings in the Torre de la Parada, commissioned by Philip IV, who is in turn the subject of a portrait attributed to Gaspar de Crayer.