Isaac Mizrahi is an American fashion designer, actor, singer, television presenter and chief designer of the Isaac Mizrahi brand for Xcel Brands. Based in New York City, he is best known for his eponymous fashion lines. Mizrahi was previously a judge on Project Runway All Stars. In 2022 he played Amos Hart in the long-running Broadway revival of Chicago.

Project Runway All Stars is an American reality television series, and a spin-off of Project Runway, featuring returning designers competing for grand prizes. Angela Lindvall and Carolyn Murphy have each hosted one season before Alyssa Milano became the staple host of the past five seasons. As on Project Runway, the designers are judged by the host, two permanent judges and guest judges throughout the season. The permanent All Stars judges have been designers Georgina Chapman and Isaac Mizrahi. Joanna Coles mentored the designers throughout seasons one and two, Zanna Roberts Rassi replaced her in season three to five and Anne Fulenwider mentored seasons six and seven.