The radio frequency (RF) electromagnetic spectrum is an aspect of the physical world which, like land, water, and air, is subject to usage limitations. Use of radio frequency bands of the electromagnetic spectrum is regulated by governments in most countries, in a Spectrum management process known as frequency allocation or spectrum allocation. Radio propagation does not stop at national boundaries. Giving technical and economic reasons, governments have sought to harmonise the allocation of RF bands and their standardisation.
A number of forums and standards bodies work on standards for frequency allocation, including:
* International Telecommunication Union (ITU)
* European Conference of Postal and Telecommunications Administrations (CEPT)
* European Telecommunications Standards Institute (ETSI)
* International Special Committee on Radio Interference (Comité international spécial des perturbations radioélectriques - CISPR)
High-demand sections of the electromagnetic spectrum may sometimes be allocated through auctions