The picture had a two-week rehearsal period in which, during this time, writer Neil Simon customized the screenplay to tailor the lead stars' personalities. During the two-week rehearsal period, Simon observed the needs of his stars and was able to re-write portions of the script to better suit their individual personalities. "There is a terrific quality about Chevy (Chase)," says Simon, "He's the bad boy in class. You never know what he is going to do. I tried to capture that in the script and in each day's re-writes."
Marsha Mason and Burt Reynolds were touted as the leads in this movie according to this film's early publicity. These roles were eventually cast though with Goldie Hawn and Chevy Chase instead.
According to Turner Classic Movies, The Talk of the Town (1942) was a major inspiration for Neil Simon.
While making this movie, Goldie Hawn was going through a divorce from Bill Hudson (Kate Hudson's father) , and overseeing post-production on Private Benjamin (1980), in which she starred, and executive produced.