The Establishment generally denotes a dominant group or elite that holds power or authority in a nation or organization. The Establishment may be a closed social group which selects its own members or specific entrenched elite structures, either in government or in specific institutions.
The American Sociological Association states that the term is often used by those protesting a small group that dominates a larger organization. For example, in 1968 a group of academics set up the "Sociology Liberation Movement" to repudiate the leadership of the American Sociological Association, which they referred to as the "Establishment in American sociology".
In fact, any relatively small class or group of people having control can be referred to as The Establishment; and conversely, in the jargon of sociology, anyone who does not belong to The Establishment may be labelled an "outsider".
Anti-authoritarian and anti-establishment ideologies tend to view establishments as illegitimate.
The term is most often used in the United Kingdom, in which context it includes leading politicians, senior civil servants, senior barristers and judges, aristocrats, Oxbridge academics, senior clergy in the established Church of England, the most important financiers and industrialists, governors of the BBC, and the members of and top aides to the royal family. For example, candidates for political office are often said to have to impress the "party establishment" in order to win endorsement. The term in this sense is sometimes mistakenly believed to have been coined by the British journalist Henry Fairlie, who in September 1955 in the London magazine The Spectator defined that network of prominent, well-connected people as "the Establishment", explaining:
By the Establishment, I do not only mean the centres of official power—though they are certainly part of it—but rather the whole matrix of official and social relations within which power is exercised. The exercise of power in the United Kingdom (more specifically, in England) cannot be understood unless it is recognized that it is exercised socially.