Billy Crystal had written the part of Eddie for himself years ago, but director Joe Roth persuaded Crystal to take on the role of Lee the publicist, as he felt Crystal was too old to play the part by then.
This was Joe Roth's first picture as director in 11 years. Initially Billy Crystal was slated to direct the picture. When Roth read the script, he was totally immersed and liked the script so much that he wanted to direct. Crystal granted Roth's request to direct the picture and stayed on as producer.
When Hal is talking to the press at the press junket his microphone shorts. As he says the line "...this is the most honest movie I have ever made" after the word "made" you hear a click and can see the flash in the microphone headpiece as it shorts.
Steve Pink who played John Cusacks limo driver also played John Cusacks classmate in Grosse Point Blank. Pink was also a screenwriter for high fidelity and directed Hot Tub Time Machine, both starring John Cusack.
When Dave (Stanley Tucci) enters the hotel bar to speak with Lee (Billy Crystal), Dave says to the bartender "I'll have whatever he's having." This is an in-joke in reference to the famous "I'll have what she's having" scene in "When Harry Met Sally" (1989), which also starred Crystal.