The fashion industry is on a relentless pursuit to answer the question: What does luxury mean today? When I joined the actress and activist Emma Watson on a fitting for the custom-made Calvin Klein dress she wore to the Met gala in New York, she had a suggestion.

“Luxury to me means peace of mind,” she said. Specifically, knowing that what she is wearing has been ethically sourced and produced.

For the past few years, Watson has resolved that all of her red carpet appearances incorporate sustainable fashion.

In the case of the Met gala, this meant the majority of the fabric used was made from Newlife, a yarn made from 100 percent post-consumer plastic bottles; and the detailing on the bustier was made with organic silk and cotton.