This time she added an extra touch of eco-friendliness by demonstrating that even though another red carpet regular had worn it before it was more than capable of making a second appearance.
Sounding excited (if a little jittery) she tweeted: "SLIGHTLY nervous 4 my dress tonight! One of my favorite designers #GreenCarpetChallenge but oh my....!!!!!"
We're sure Colin was on hand to give a nice reassuring hug though as there was no trace of nerves in the red carpet pictures we've seen.
And for more fashion repeats, just click through the gallery below: