Each syllable of the musical solfège system appears in the song's lyrics, sung on the pitch it names.
Rodgers was helped in its creation by long-time arranger Trude Rittmann who devised the extended vocal sequence in the song.
According to assistant conductor Peter Howard, the heart of the number—in which Maria assigns a musical tone to each child, like so many Swiss bell ringers—was devised in rehearsal by Rittmann (who was credited for choral arrangements) and choreographer Joe Layton.
"[2] In the stage version, Maria sings the song in the living room of Captain von Trapp's house shortly after she introduces herself to the children.
[7] When The Sound of Music was translated to German in 2005 for the Vienna Volksoper, the song "Do-Re-Mi" was rewritten as "C wie Cellophanpapier".