Reed has been a member of Chicago's Steppenwolf Theatre Company for many years, appearing in 51 productions with the company. She appeared on Broadway in The Rise and Fall of Little Voice in 1994 and The Grapes of Wrath in 1990, among others. On July 13, 2005, she originated the role of Madame Morrible in the Chicago production of the musical Wicked.
She originated the role of Mattie Fae Aiken in the Broadway production of August: Osage County in 2007, for which she won the 2008 Tony Award for Best Performance by a Featured Actress in a Play.
She later reprised her role of Madame Morrible in Wicked in Chicago, beginning June 27, 2008. Her second run ended November 18, 2008 and she was again replaced by Robertson. She then reprised her role as Mattie Fae Aiken in the London production of August: Osage Country before returning to Madame Morrible in the Broadway production of Wicked. She began performances March 17, 2009, replacing Jayne Houdyshell and bowed out as the evil headmistress on June 27, 2010, to star in the Australian production of August in Sydney. The limited engagement of the show ran from August 13-September 25, 2010. She returned to the New York production of "Wicked" from July 31, 2017 to January 28, 2018.
She appeared in the Seinfeld episode "The Kiss Hello" (originally aired on February 16, 1995). She starred on the CBS sitcom Mike & Molly, as Peggy Biggs, Mike's mother. She also appeared on Roseanne as Jackie's therapist.
2020
as Irene
2019
as Mrs. Yost
2016
as Nina
2016
as Michaela
2015
as Nadine
2014
as Victoria Harper
2013
as Edith Schiff
2013
as Jolene
2012
as Mary Peterson
2010
as Margaret 'Peggy' Biggs
2010
as Judge Cooper
2008
as Lana
2003
as Roy's Sister Beth
1999
as Dr. Conlin
1997
as Sarah
1997
as Suzanne Carroll
1995
as Eunice
1993
as Veronica Castane
1993
1993
as Detective Chelsey
1993
as Victoria Penny
1992
as District Attorney
1991
as Dr. Miller
1989
as Mary
1986
as Nancy Lapine
1986
as Mrs. Becker
1982
1956
as Self - Winner