Natalie Portman was the only member of the cast to wear a safety harness on the crane in the quarry. Because of her size, the crew was afraid she would slip and fall.
Writer and director Zach Braff chose to not include a full love scene between him and Natalie Portman because he felt it would take the audience out of the movie too much. He wanted it to be implied and sweet rather than visual.
The tombstones in the pet cemetery were made by the cast and crew, and feature their own deceased pets' names.
Natalie Portman was so embarrassed about the tap dancing scene that she made Zach Braff promise if it was bad that he would cut the scene entirely.
The depiction of Andrew Largeman (Zach Braff) working in a Vietnamese restaurant was from Braff's own experience. He worked as a waiter in a French-Vietnamese restaurant when he auditioned for the leading part in the series Scrubs: Die Anfänger (2001).