Ivan Reitman had already collaborated with Bill Murray and Harold Ramis when he set to work on Ghostbusters. Ramis co-wrote Stripes and Meatballs, two Reitman films that had both starred the comedy hero Bill Murray. Reitman was known for giving broad comedies a playful spin, and another one of his major successes had been as the producer of the iconic frat comedy National Lampoon's Animal House. Interestingly enough, the idea for Ghostbusters didn't begin with Reitman or Murray or Ramis, but with the film's other star, Dan Aykroyd. Aykroyd had envisioned the film as a big-budget vehicle for himself and John Belushi, but Belushi died before work on the film began.
When Aykroyd pitched his idea to Reitman, it was full of space and time travel, multiple dimensions, and other paranormal excesses. While Reitman was very excited about the idea of a group of Ghostbusters, he brought Aykroyd down to the earth, insisting that they find a way to keep the film within a practical budget. Reitman had a huge influence on the edits that Ramis and Aykroyd made to the script of the film. Reitman hired a number of accomplished illustrators and visual effects specialists to fill out and illustrate the ghostly New York of the film.
The film did not always get along so well with New York City and its residents, and Ghostbuster's truncated production time only made this more tense. Particularly the scenes shot on Central Park West caused a lot of disruption and yielded many complaints from residents, who saw the film shoot as a major problem. Traffic jams and crowded streets ruffled the feathers of many Upper West Side residents, including science fiction writer Isaac Asimov, who happened to be one of Dan Aykroyd's idols. When Aykroyd approached Asimov in the street, Asimov paid him little mind and wanted to know if he was responsible for the traffic jam taking place.
Reitman was a competent and assured leader, and in spite of the stumbling blocks that the film faced, the atmosphere on set was jovial and enjoyable, and they even finished shooting the scenes on Central Park West, a full two days ahead of schedule. Ghostbusters remains Ivan Reitman's most notable and influential film to date.