A wise man named Justin Timberlake once said, "What goes around . . . comes all the way back around," and this rings particularly true in the world of fashion. After a 2018 filled with '90s-inspired choker necklaces, mom jeans, and denim skirts, 2019 will shine a spotlight on pieces that pay homage to the 2000s. Think fresh, modern takes on the cargo pants Christina Aguilera wore on the red carpet and updated versions of the low-slung trousers Britney Spears paired with midriff-baring crop tops circa her "Toxic" days. These trends from the early aughts popped up on the Spring 2019 runways, with designers like Alexander Wang and Zimmermann showing us how they can be surprisingly sexy.