Cartels tend to spring from oligopolistic industries, where a few companies or countries generate the entire supply of a product. This small production base means that each producer must evaluate its rivals' potential reactions to certain business decisions. When oligopolies compete on price, for example, they tend to drive the product's price throughout the entire industry down to the cost of production, thereby lowering profits for all producers in the oligopoly. These circumstances give oligopolies strong incentive to collude in order to maximize their joint profit.
Members of a cartel generally agree to avoid various competitive practices, especially price reductions. Members also often agree on production quotas to keep supply levels down and prices up. These agreements may be formal or they may consist of simple recognition that competitive behavior would be harmful to the industry.
Ironically, each member of a cartel has an economic incentive to cheat on any collusive agreements that are reached. For example, some companies or countries may choose to cheat on production quotas -- thereby enabling them to sell more of a particular product at higher prices (prices that are, of course, driven artificially higher when other members adhere to the agreed-upon production quotas). Another way members often cheat on the cartel is to lower prices. An undetected price cut will help a company to attract customers who are buying from the other members, as well as customers who are not buying the product at all. Some of these price adjustments may be subtle, including better credit terms, faster delivery, or related free services.
Cartels have less control than monopolies, where only one company or country manipulates supply. For this reason, prices in oligopolistic industries are generally not as high as they would be at the monopolistic level. However, prices are usually well above those that exist in purely competitive markets.
