The movie and its source book were based on the case of six-year-old Etan Kalil Patz. He disappeared in Manhattan on May 25, 1979, while walking 2 blocks to a school bus stop. He was the first missing child to be advertised on a milk carton. The case launched the missing children's movement, new legislation, and new methods for locating missing children.
Kate Nelligan once said of her character in this movie that it was "all the things that actors want to find on their doorstep. Susan is an emotionally and morally gifted woman with an abundance of dignity and intelligence."
The script originally had Alex Selky's estranged parents reconcile at the end. Those scenes were cut.
This movie has one of the early bit parts of William H. Macy. He is credited as one of the reporters, and is seen just after the bathtub scene with Kate Nelligan ends. In the next scene, she is leaving her apartment and a crowd of reporters and police are outside. Macy is standing on the sidewalk facing the street speaking into a camera. As Nelligan walks around and enters the car, he is seen running around the back of the car.
Prior to writing this movie's source "Still Missing" novel, its author Beth Gutcheon spent a considerable amount of time doing research. This included compiling masses of newspaper accounts about missing children and reading copious volumes of police texts and crime victim sociological studies.