Collusion is an agreement, usually secretive, which occurs between two or more persons to deceive, mislead, or defraud others of legal rights. If the agreement is to commit a crime in the future, such collusion may be a criminal conspiracy.

Collusion may also refer to:

Collusion (EP), a 2005 metalcore album Collusion Syndicate, a defunct special interest group Collusion (software), later called Lightbeam, an experimental add-on for Firefox and Google Chrome Collusion (psychology), a behavioral pattern in relationships

See also Collision (disambiguation)