For the house in which most of the film takes place, two real houses in Winston-Salem were used, one for internal shots and another for external ones. Filming was simplified by the fact that the two houses were down the street from each other. The same house that was used for the external shots was also used for the basement/garage scenes. The exterior house also housed the makeup department.
In the scene where Ashley (Amy Adams) does her sit up exercises, director Phil Morrison used a split screen, combining the performance of a real pregnant woman with Adams's head.
The painting that depicts the Battle of Antietem, which Embeth Davidtz is looking at when David Wark is first introduced, depicts (in one corner) two young girls huddling together with the words "An Unseen Enemy" written above them. This is clearly a reference to the D.W. Griffith film An Unseen Enemy (1912), with the two girls depicted being Lillian Gish and Dorothy Gish. This detail can be briefly glimpsed in the scene, but a close up of it can be seen in the Outsider Art Gallery section of the DVD. On a side note, the initials in D.W. Griffith's name stand for David Wark.
Alessandro Nivola missed the reference to his character singing a hymn when he read the script, and was unaware that he had to do so until a few days before his "singing scene" was scheduled to shoot. He only had a few days to rehearse, and his singing in the scene is recorded live, as the budget did not allow for it to be recorded on a sound stage.
Embeth Davidtz was chosen as a replacement at the 11th hour and arrived on set the day before principal photography began.
Ashley's monologue about cheer leading and meercats was used for Amy Adams's audition. The scene was also later used on the talk-show circuit when Adams was promoting the film.