A gatekeeper is a person who controls access to something, for example via a city gate. In the late 20th century the term came into metaphorical use, referring to individuals who decide whether a given message will be distributed by a mass medium.
Gatekeepers serve in various roles including academic admissions, financial advising, and news editing. An academic admissions officer might review students' qualifications based on criteria like test scores, race, social class, grades, family connections, and even athletic ability. Where this internal gatekeeping role is unwanted, open admissions can externalize it.
Various gatekeeping organizations administer professional certifications to protect clients from fraud and unqualified advice, for example for financial advisers.
A news editor selects stories for publication based on his or her organization's specific criteria, e.g., importance and relevance to their readership. For example, a presidential resignation would be on the of a newspaper but likely not a celebrity break-up (unless the paper was of the gossip variety).
Other people gatekeeping roles in mental health service include clergy, police, hairdressers, and bartenders because of their extensive contact with the public.
Gatekeeper is also a term used in business to identify the person who is responsible for controlling passwords and access rights or permissions for software that the company uses.