Hundreds of thousands of students and young people from all over the world took to the streets today to protest climate change and global warming. It was so refreshing, then, to see a fashion show put sustainability front and center, from the fabrics in the clothes to the way the set was produced. Repurposed materials such as the seats and stage props were from past shows, and many of the clothes used upcycled fabrics from leftover parts. The results are still visually arresting, with Marni Creative Director Francesco Risso's eye for color, off-kilter proportions and utterly chic dresses commanding the runway today. Here's everything else you need to know about the Spring 2020 collection.