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.
 Gatekeeping roles
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.
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 front page of a newspaper but likely not a celebrity break-up (unless the paper was of the gossip variety).
 Academic peer review
Peer review is a practice widely used by specialized journals that publish articles reporting new research, new discoveries, or new analyses in a specific academic field or area of focus. Journal editors ask one or more subject matter experts deemed to be "peers" of an article's author or authors to assess an article's suitability for publication in the journal. Notwithstanding the fact that the intent of peer review is to insure suitability and editorial quality, issues of preference or exclusion of articles are raised from time to time relating to the intellectual prejudices, career rivalries, or other biases of the journal editors or peer reviewers.
Credentialing is the practice of evidencing suitability for engaging in a profession or for employability through documentation of demonstrated competency or experience, completion of education or training, or other criteria as specified by a credentialing authority. The documentation provided by the authority are known as "credentials", and may be in the form of a license, certificate of competency, a diploma, a teaching credential, a board certification, or a similar document. Credentialism refers to the practice of relying on credentials to prove the suitability of a professional person or a skilled employee to be assigned the responsibilities of professional engagement or employment.