George Gershwin (1898-1937) wrote an opera about black life, and he called it a "folk opera." This opera became the work now famously known as Porgy and Bess. But, rather than use traditional black folk music, Gershwin wrote his own music that emulated the African-American folk style. The result is a work comprising recitatives, solo arias, and ensemble and choral pieces that reference musical and stylistic features of the African-American spiritual. This paper will explore how Gershwin acquired knowledge of the musical materials and stylistic features of African-American choral arrangements of spirituals to influence his own representation of spirituals in Porgy and Bess. The paper will compare particular settings of spirituals published during the 1920s and 1930s. Works by such African-American composers as Harry T. Burleigh (1866-1949), R. Nathaniel Dett (1882-1943), and Hall Johnson (1888-1970) will be examined in context with selected choruses from Porgy and Bess. Scholars agree that Gershwin had a special talent for employing black music idioms in his compositions and possessed a penchant for combining musical styles. As black music was popular during the Harlem Renaissance, it might be expected that Gershwin would effectively incorporate black folk music traditions in his opera. Gershwin lived and worked during this seminal period of the African-American spiritual. Prior to Gershwin's birth, the concert arrangement of the spiritual had gained prominence with its introduction by the Jubilee Singers of Fisk University in Nashville, Tennessee. In 1871, the singers achieved renown by their reputable fund-raising concert tours throughout the United States and abroad. In the 1920s and 1930s the Harlem Renaissance was in full flowering, and published arrangements of spirituals were widely distributed and commonly heard in concerts, on film, and on radio broadcasts throughout America. Simultaneously, musical theater was at its peak, and notable concerts, featuring concert music of black composers by black performers were staged in New York. Gershwin owned published collections of spiritual arrangements, and had professional and personal associations with black musicians and composers from which he could further draw inspiration for his work on Porgy and Bess. Gershwin traveled to South Carolina twice, with librettist DuBose Heyward as guide, between 1933 and 1934, to hear and absorb the musical traditions of the Gullahs, the people on whom Gershwin based the opera's characters. Some of the music (i.e. "Oh, Doctor Jesus") was directly influenced by what Gershwin heard in South Carolina. The Gullah, or low-country spirituals featured in Heyward's novel (and subsequent play Porgy) were influential as well. An examination of several choral pieces from the opera reveals also the impact Gershwin's exposure to African-American choral arrangements of spirituals had on his creative imagination. Shortly after the premiere of Porgy and Bess, Gershwin explained in a New York Times article that he composed his "own spirituals" for the opera rather than insert traditional African-American folk songs because he wanted the music to be "all of one piece." Implicit in Gershwin's statement is the desire to create consistency in musical sound and style. So, he wrote several pieces in the style of spirituals to ensure musical continuity throughout the opera. In particular, several of the choral pieces show clear evidence of the influence of the choral arrangements of spirituals by African-American composers. These spirituals proliferated just prior to and during the time that Gershwin composed the opera. Finally, this paper will review the performance practice of spirituals, as revealed through recordings and as described by noted black scholars. It is the belief of this author that such detailed information can provide performers and scholars with an historical basis for choosing, studying, understanding, and performing choral excerpts from Porgy and Bess in ways that accurately reflect African-American folk music traditions.