During one take, when Condorman falls into the River Seine, Michael Crawford nearly drowned after the strength of the current was miscalculated. He was dragged five to ten feet under the water before two lifeguards pulled him out just in time. Crawford was willing to do the stunt again but director Charles Jarrott refused to allow it, and put a trained stuntman in his place.
One night, after one too many alcoholic drinks, Oliver Reed tossed his tuxedo costume into the sea from a Monte Carlo hotel room. When the company manager found out the next morning, he rowed out into the Mediterranean to retrieve it before it floated away.
When Woody is glamorizing Harry's job at the CIA, Harry responds, "Not everyone in the CIA is Robert Redford." This is a subtle joke about Les 3 jours du Condor (1975), in which Redford plays a CIA agent whose codename is Condor.
Relaxing one night after a long day of filming, Oliver Reed was relaxing when Michael Crawford was walking by. Oliver, in his character's Russian accent, invited Michael to sit and have a drink. When Michael declined, Oliver demanded saying, "Come here into Russian Embassy and have drink, you little feathered fart!". Needless to say, from that moment on Michael was referred to as "Condorman the Feather Fart."
Jean-Pierre Kalfon wore a specially made contact lens for his role of Morovich, which gave him the appearance of having a metallic eye.