The Russian Revolution brought an end to the financial support Sonia received from her family in Russia, and a different source of income was needed. In 1917 the Delaunays met Sergei Diaghilev in Madrid. Sonia designed costumes for his production of "Cleopatra" (stage design by Robert Delaunay) and for the performance of Aida in Barcelona. In Madrid she decorated the "Petit Casino" (a nightclub) and founded "Casa Sonia", selling her designs for interior decoration and fashion, with a branch in Bilbao. She was the center of a Madrid Salon.