Libretto translation is a formidable task. In addition to mediating between the source language and target language, the translator must also work with a strict set of musical parameters. Many critics seem to agree that musical considerations must prevail over the text. But to what degree can semantic flexibility be attributed to musical constraints? And what impact will loyalty to the music ultimately have on the significance of an opera? In order to shed some light on those questions, this paper presents a critical analysis of the original French and English translations of Puccini's opera, "Madama Butterfly". Through a text-based analytical approach, this paper challenges the notion that altering the meaning of a libretto is acceptable as long as the text conforms to the music.