The Marshall Field's Day of Music begins at noon and includes jazz, pop, and classical performances in and around Orchestra Hall. The day culminates in a free concert led by music director Osmo V‹nsk‹ and featuring violinist Pekka Kuusisto. The program includes Grieg's Peer Gynt Suite No. 2, a series of Silbelius Humoresques, and Beethoven's Eighth Symphony. Concertgoers are urged to line up early.

Sommerfest runs through August 7. Andrew Litton, the festival's music director, will lead six programs; V‹nsk‹ will lead two, including tonight's concert. The two will also perform together in a chamber music concert, with Litton performing at the piano and V‹nsk‹ making a rare appearance on the clarinet.

Other highlights include a 25th-anniversary celebration featuring the same program of Strauss waltzes and polkas that opened the first Sommerfest in 1980. Soprano Heidi Grant Murphy is the soloist. Pianist Christopher O'Riley makes three appearances, two with the orchestra and one performing his trademark solo piano arrangements of songs by the rock band Radiohead.

Other soloists include soprano Harolyn Blackwell, appearing in Orff's Carmina Burana, and Kevin Cole, playing Gershwin's Piano Concerto in F and Rhapsody in Blue.