The 47-year-old girlfriend of Mick Jagger was discovered by her assistant hanging from a scarf tied to a doorknob in her 11th Avenue apartment in New York City at around 10 a.m.
Police did not find a suicide note and do not suspect foul play.
Scott, a former model, was best known for dressing the likes of Nicole Kidman, Amy Adams, Christina Hendricks and Penelope Cruz for red carpet events.
A spokesperson for Jagger told Us Weekly that the Rolling Stones singer is currently in Australia and is "completely shocked and devastated by the news."
Jagger and Scott had been dating since 2001.
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