One trailer for this movie consisted entirely of bloopers.
Lesley-Anne Down was cast as Olga by mistake. Writer, producer, and director Blake Edwards meant to audition Nicola Pagett, who played Elizabeth Bellamy on Upstairs, Downstairs (1971), but auditioned Down, who played Georgia Worsley on later episodes of that same series. Dame Julie Andrews commented that she didn't look like the actress in the series, but Edwards blamed the lighting and make-up.
Omar Sharif, who had just worked with writer, producer, and director Blake Edwards on The Tamarind Seed (1974), has a brief cameo as the Egyptian Assassin.
Peter Sellers refused to attend the London Royal Premiere because his then-girlfriend Lynne Frederick hadn't been invited. King Charles III was annoyed at Sellers' non-appearance, but admitted that he really enjoyed this movie.
The opening credit sequence includes the Pink Panther substituting for Dame Julie Andrews in her famous The Sound of Music (1965) role. Andrews was married to writer, producer, and director Blake Edwards from November 12, 1969 until his death on December 15, 2010.