A cartel is a united group of industrial corporations which band together for the purpose of restricting trade for their mutual benefit. Cartels may agree to control distribution, set prices, reduce competition, and sometimes share technical expertise. Such companies usually are international and cartels generally exist outside of the United States, since U.S. antitrust laws generally prohibit the formation of cartels.
The most well-known cartel is OPEC (Organization of Petroleum Exporting Countries), which represents all of the oil producing countries in the Middle East, North Africa and Venezuela. Some cartels operate secretively, such as illegal drug cartels.