A market structure characterized by many firms selling differentiated products where each firm has some degree of market power but no long-term economic profit.
The degree of control that a buyer exerts in a market, primarily measured by the concentration of the industry. It is the counterpart of monopoly power.
An international agreement reached in 1987 to reduce the production and consumption of chlorofluorocarbons (CFCs) and halon, substances which deplete the ozone layer in the upper atmosphere.