Kathryn "Kathy" Mullen is a puppeteer and actress who worked on many Jim Henson projects. Mullen joined the Muppets in 1978, starting with The Muppet Movie, and later became a full-time puppeteer on The Muppet Show. She advanced to performing major roles on Fraggle Rock, where she played Mokey Fraggle and Cotterpin Doozer, among others.
She later worked with The Jim Henson Company on The Wubbulous World of Dr. Seuss, and was one of the creators and performers of the PBS series Between the Lions. In 2004, she and husband Michael Frith worked with No Strings International to create and perform an educational puppet show for children in Afghanistan.