Perhaps Szigeti's most fruitful musical partnership was with his friend Béla Bartók. The first piece Bartók dedicated to him was the First Rhapsody for violin and orchestra (or piano) of 1928; the rhapsody, based on both Romanian and Hungarian folk tunes, was one of a pair of violin rhapsodies written in 1928 (the other being dedicated to Zoltán Székely.) In 1938, Szigeti and clarinetist Benny Goodman teamed up to commission a trio from Bartók: originally intended to be a short work just long enough to fill both sides of a 78 rpm record, the piece soon expanded beyond its modest intent and became the three-movement "Contrasts" for piano, violin and clarinet. In 1944, by which time Szigeti and Bartók had both fled to the United States to escape the war in Europe, Bartók's health was failing and he had sunk into depression. He was in dire need of money, but felt no inspiration to compose and was convinced that his works would never sell to an American audience. Szigeti came to his friend's aid by securing donations from the American Society of Composers and Publishers to pay for Bartók's medical treatment, and then, together with conductor and compatriot Fritz Reiner, persuaded Serge Koussevitzky to commission from Bartók what eventually became his much-beloved Concerto for Orchestra. The work's success brought Bartók some measure of financial security and provided him with a much-needed emotional boost.