Michael Gerard Hagerty, also known by his stage name Mike Hagerty, is an American actor. He is known for playing comedic blue-collar workers, including his recurring roles as a building superintendent, Mr. Treeger on Friends, and the manager of a muffler shop on HBO's Lucky Louie.
Hagerty is recognized for his small character roles in a wide range of popular comedies, including Cheers, The Wayans Bros., Curb Your Enthusiasm, Friends, Seinfeld, and The Wonder Years. He was also a regular on The George Carlin Show. He began his acting career with The Second City. Although the majority of his career has been spent in television, he has had small roles in a handful of films. He is known for his mustache and thick Chicago accent.
Hagerty was born in Chicago, Illinois.