Song pluggers work for a music publishing company or operate independently.
In the late 19th and early 20th centuries, a song plugger was a vocalist or piano player employed in the early 20th century by department stores, music stores and song publishers to promote and help sell new sheet music.
Music publisher Frank Harding has been credited with innovating the sales method.
"[citation needed] Notable musicians and composers who had worked as song pluggers included George Gershwin,[1][3] Ron Roker,[citation needed] Jerome Kern,[4] Irving Berlin,[1] Lil Hardin Armstrong,[5] Irving Mills,[6] and Cole Porter.
[9] In 1952, Life writer Ernest Havemann noted the following: There are about 600 song-pluggers in the U.S.; they have their own union; they are powerful enough to bar all outsiders; and they command fees up to $35,000 a year [worth $414,430 today] plus unlimited expense accounts.