Mary was an intern and a cocktail waitress while pursuing her acting career.
Mary graduated from Wardlawy-Hartidge School in 1987.
Mary's parents divorced in 1990.
Mary worked with the following stage companies:
-The Atlantic Theatre Company
-Alice's 4th Floor
Mary appeared with her brother William McCormack in the 1997 independent film Colin Fritz.
Mary and her husband have two children, one born in 2004, and the other in 2007.
Mary replaced actress Kate Walsh in the film 1408 after Walsh had to drop out of the project.
Mary is 5' 8" (1.73 m).
Mary is of Irish descent.
As of 2007, all of the movies Mary has appeared in have grossed a total of $333,144,910.
Mary studied acting at the William Esper Studio.
Mary was nominated twice for Best Ensemble Cast at the Screen Actors Guild for her work on The West Wing in 2005 and 2006.
Mary made her feature film debut in the 1994 remake of A Miracle on 34th Street.
Mary is the sister of actor Will McCormack.
She was married in the summer of 2003.
Mary attended Trinity College, majoring in English.
Mary began her acting career at age 12 performing in Gian Carlo Menotti's Christmas opera, Amahl and the Night Visitors.
[On if it was difficult ending The West Wing]
Mary McCormack: For that amount of time it was difficult but for the rest of the cast and the crew it was like a lifetime. I felt lucky to be there even for as short a time as I was there. The fans were amazing and it was just nice to be on a show that people were watching and talking about. It was a great role and I worked with Allison Janney mostly who's now one of my best friends so it was a great experience.
[On her character ftom Traffic]
Mary McCormack: It's interesting that throughout the show, many characters say, 'I'm just the middle man.' Through our apathy we are all middle men — every time you hire someone to cut your lawn who you don't pay benefits to, you are a middle man. We are all sort of responsible. I thought the show did a really amazing job in pointing out how we are all complicit.
[On getting the part in the play Amahl and the Night Visitors]
Mary McCormack: I was twelve but looked like an eight-year-old boy. As luck would have it, none of the boys in town could sing, so I got the part and wore a hat.
[Explaining what a slammer girl is]
Mary McCormack: I'd wear cutoff shorts and a bra--well, a halter top, but like a bra, with the midriff showing, you know? And I'd wear a holster with tequila on one side and 7Up on the other, and I'd wear a bandoleer with shot glasses, and I'd walk around the bar and go up to a guy.