A group of people who share common traits, attitudes, beliefs, and/or objectives who have formed a formal organization to serve specific common interests of the membership. Examples of interest groups would include such disparate organizations as the Auburn Chamber of Commerce, the Society for the Prevention of Cruelty to Animals, the elementary school P.T.A., the Teamsters Union, the Southern Baptist Convention, the American Numismatics Association, the National Association for the Advancement of Colored People, the Brangus Breeders Association, the American Civil Liberties Union, the Cosa Nostra, and the Benevolent Order of Elks. Interest groups typically have formal admission to membership, dues, elected officers, by-laws and regular meetings, and they often provide information and regular opportunities for communication through newsletters or magazines, sponsor recreational or educational activities, organize volunteer public service projects, make deals for group discounts or group insurance and so on. Larger interest group organizations may have full-time paid officers or professional staff to manage and to supplement the efforts of member-volunteers in furthering the work of the organization. Many interest groups at least occasionally engage in some form of lobbying or other political activities with respect to issues that touch directly on the common interests that are the organization's reason for being -- for example, the PTA may organize support for a bond issue election to pay for erecting a new school building. Some interest groups have political activity as their principal or only reason for being in the first place. Interest groups that exist primarily for exerting political influence as a means of affecting government policies or legislation are often referred to by the narrower term pressure groups. Since more and more activities have become politicized with the expansion of the scope of activities of the government in the 20th century, more and more interest groups find themselves drawn into politics to protect or promote the interests of their membership, and the distinction in usage between the terms interest group and pressure group has accordingly become less significant in ordinary language.

[See also: pluralist theory]