From Renaissance courtesans swathed in gold cloth to Victorian debutantes corseted in rich silks: from flappers swinging beaded hems and Hollywood starlets draped in lame to today's red-carpel goddesses, women have transformed themselves for night. Even Coco Chanel, renowned for her comfortable daywear, saw evening fashion as something quite separate, not to be constrained by matters of practicality. "Be a caterpillar by day and a butterfly at night", she advised. "Nothing could be more comfortable than a caterpillar and nothing more made for love than a butterfly".