Lives in West Hollywood, California with her poodles, Willa and Elmo.

She is the lead singer in the LA band, The Supreme Music Program.

She recently starred in and directed an original performance art piece, The Sweetheart Break-In. The band released a CD of some of the songs in the show, called 'The Supreme Music Program: The Sweetheart Break-In'.

Graduated from Casady High School, Oklahoma City, Oklahoma.

Her father, Carter Mullally Jr., who died in the late 90s, was a contract player with Paramount in the 1950s. Her mother, Martha, is a former model.

Megan announced her engagement to actor Nick Offerman in September 2002.

Close friend is "ER" (1994) actress Laura Innes. The two met at Northwestern University in the late 70s and have been friends ever since.

She studied ballet and was a soloist with Oklahoma City's Ballet Oklahoma. She also studied at George Balanchine's School of American Ballet.

Auditioned for the role of Elaine on "Seinfeld" (1990). (According to the Seinfeld special, aired on 25 November 2004.)

Attended Northwestern University

Has won 3 consecutive Screen Actors Guild Awards (SAG) for Outstanding performance by an actress in a comedy, and has a total of 4 SAG Awards and an Emmy Award.

First cast member of "Will & Grace" (1998) to win an Emmy. She won in 2000 for Outstanding performance by an actress in a supporting role comedy. Her co-star, Sean Hayes, also won that year.

Originally auditioned for "Grace" on "Will & Grace" (1998), but was later cast as "Karen".

Was featured in "Theater Week" as one of six "New Faces of 1995," alongside Rufus Sewell, Jude Law, Jennifer Dundas, Justin Kirk, and Billy Crudup.

Ironically, she stated in that issue that she was done with television, and in five years would like "to be doing plays and musicals [in New York], and also film work."

She almost wound up in the role of Carrie in "The King of Queens" (1998).