Most movie music is selected by a music director for movies, business management professionals, also called music supervisors. They oversee the composer and other musicians involved in creating music for a movie, and select music to create the atmosphere of a movie through the soundtrack selection.
There is a Grammy for music supervision, and now an Emmy. No Oscar yet, but the real prize for this industry is the Guild of Music Supervisors Awards.
Whether it was Sia’s “Breathe Me” on Six Feet Under, or “Zou Bisou Bisou” on Mad Men, or that infamous OC scene with Imogen Heap’s “Hide and Seek,” a well-placed song can amplify the emotional intensity and resonance of a moment, elevating it to fame. And while a flawless pairing of scene and soundtrack can feel perfectly serendipitous, these moments are almost always the result of someone poring through thousands of tracks and spending hours working with the show’s creative team to find exactly the right tune, to say nothing of securing permission to use it. That’s the job of the music supervisor, in a nutshell. (What a great career! Discovering obscure music cuts all day long for a living.)
If you think it isn’t important, ask one hit wonder Smash Mouth. The music director for Shrek picked up their song “All Star” in 2001, and it has played more or less continuously on the radio, and apps, for 20 years.