Agency may refer to:

* Agency (country subdivision)
* Agency (law), refers to a person who acts on behalf of another person.
* Agency (Mormonism)
* Agency (sociology), the ability of social actors to make independent choices.
* Agency (philosophy), relating to action theory (philosophy).
* Advertising agency, a service business dedicated to creating, planning and handling advertising for its clients.
* Employment agency, a business that serves as a representative, acting on behalf of another.
* Free agency, the availability status of a rostered player on a team or franchise who is a free agent.
* Government agency, a department of a local or national government responsible for the oversight and administration of a specific function.
* International agency, an inter-governmental body.
* News agency.
* Moral agency, capacity for making moral judgments.
* Structure and agency, ability of an actor to organize future situations and resource distribution.
* Agency (film), a 1980 film starring Lee Majors.
* bond (finance), a debt security, in which the authorized issuer owes the holders a debt.

Organizations
* Central Intelligence Agency (CIA), colloquially called "the Agency"
* Food and Drug Administration (FDA), colloquially called "the Agency"
* International Atomic Energy Agency (IAEA) (when context allows this abbreviation without ambiguity; official term for internal use)