Rate fixing is collusion to manipulate a market rate for the advantage of those participating in the collusion, usually harming other market participants.
This is illegal in almost all jurisdictions and markets.
Examples include the illegal fixing of LIBOR rates, and the WMR scandal relating to foreign exchange rates.
The term may also be used for the calculation and publication of a market reference rate by a legitimate authority.
The legitimate establishment of a rate to be used in a contract, under the terms of the contract, often by reference to a market benchmark rate.