When Monteverdi composed L'Orfeo he had a thorough grounding in theatrical music.
He had been employed at the Gonzaga court for 16 years, much of it as a performer or arranger of stage music, and in 1604 he had written the ballo Gli amori di Diane ed Endimone for the 1604–05 Mantua Carnival.
The elements from which Monteverdi constructed his first opera score—the aria, the strophic song, recitative, choruses, dances, dramatic musical interludes—were, as conductor Nikolaus Harnoncourt has pointed out, not created by him, but "he blended the entire stock of newest and older possibilities into a unity that was indeed new".
Musicologist Robert Donington writes similarly: "[The score] contains no element which was not based on precedent, but it reaches complete maturity in that recently developed form ... Here are words as directly expressed in music as [the pioneers of opera] wanted them expressed; here is music expressing them ... with the full inspiration of genius."

Monteverdi states the orchestral requirements at the beginning of his published score, but in accordance with the practice of the day he does not specify their exact usage.
At that time it was usual to allow each interpreter of the work freedom to make local decisions, based on the orchestral forces at their disposal.
These could differ sharply from place to place.
Furthermore, as Harnoncourt points out, the instrumentalists would all have been composers and would have expected to collaborate creatively at each performance, rather than playing a set text.
Another practice of the time was to allow singers to embellish their arias.
Monteverdi wrote plain and embellished versions of some arias, such as Orfeo's "Possente spirto", but according to Harnoncourt "it is obvious that where he did not write any embellishments he did not want any sung".

Each act of the opera deals with a single element of the story, and each ends with a chorus.
Despite the five-act structure, with two sets of scene changes, it is likely that L'Orfeo conformed to the standard practice for court entertainments of that time and was played as a continuous entity, without intervals or curtain descents between acts.
It was the contemporary custom for scene shifts to take place in sight of the audience, these changes being reflected musically by changes in instrumentation, key and style.
When Monteverdi composed L'Orfeo he had a thorough grounding in theatrical music. He had been employed at the Gonzaga court for 16 years, much of it as a performer or arranger of stage music, and in 1604 he had written the ballo Gli amori di Diane ed Endimone for the 1604–05 Mantua Carnival. The elements from which Monteverdi constructed his first opera score—the aria, the strophic song, recitative, choruses, dances, dramatic musical interludes—were, as conductor Nikolaus Harnoncourt has pointed out, not created by him, but "he blended the entire stock of newest and older possibilities into a unity that was indeed new". Musicologist Robert Donington writes similarly: "[The score] contains no element which was not based on precedent, but it reaches complete maturity in that recently developed form ... Here are words as directly expressed in music as [the pioneers of opera] wanted them expressed; here is music expressing them ... with the full inspiration of genius."
Monteverdi states the orchestral requirements at the beginning of his published score, but in accordance with the practice of the day he does not specify their exact usage. At that time it was usual to allow each interpreter of the work freedom to make local decisions, based on the orchestral forces at their disposal. These could differ sharply from place to place. Furthermore, as Harnoncourt points out, the instrumentalists would all have been composers and would have expected to collaborate creatively at each performance, rather than playing a set text. Another practice of the time was to allow singers to embellish their arias. Monteverdi wrote plain and embellished versions of some arias, such as Orfeo's "Possente spirto", but according to Harnoncourt "it is obvious that where he did not write any embellishments he did not want any sung".
Each act of the opera deals with a single element of the story, and each ends with a chorus. Despite the five-act structure, with two sets of scene changes, it is likely that L'Orfeo conformed to the standard practice for court entertainments of that time and was played as a continuous entity, without intervals or curtain descents between acts. It was the contemporary custom for scene shifts to take place in sight of the audience, these changes being reflected musically by changes in instrumentation, key and style.
L'Orfeo