The librettist and the screenwriter

Being a librettist is a lot like being a screenwriter and neither is much like being a playwright. The librettist, like the screenwriter but unlike the playwright, knows going in that his project depends on the creative talents of others who will end up with more creative control over the project. A libretto is nothing without a composer, and in the end the music will make or break the project. The composer is like the director of a film. And although the playwright also has collaborators, the vision of the playwright wins out. The playwright retains artistic control (which is why directors prefer dead playwrights!). It's the stage director's job to realize the playwright's vision, not subordinate the material to his own vision. That's the theory and legal rules anyway. Again, stage directors love adding their own visions, which is why they like dead playwrights.