Forms of Industrial OrganizationsBased on production and sales, environmental economists group industries into market structures. There are four basic market structures, namely: (1) pure competition, (2) monopoly, (3) oligopoly, and (4) monopoly. Factors differentiating the four markets include ease of entry or exit, the number of firms within the sector, and the availability of substitutions. It is not uncommon for a market to start as one type of structure and evolve into another. The following article will discuss the four different market structures and explain the life cycle and progression of the all-optical laptop industry. Pure competition. Monopoly. Oligopoly. The third type of market structure available in today's market industry is an oligopoly. “An oligopoly involves only a few sellers of a standardized or differentiated product, such that each firm is affected by the decisions of its rivals and must take these decisions into account in determining its own price and output” ( Brue and McConnell, 2004 , pp. 3,4). Examples of oligopoly can be found in the oil industry. Shell and Texaco, for example, must consider a number of different factors when trying to increase revenue. Due to the limited number of oil companies in the market, companies must depend on low-level sellers to make price adjustments every week to capitalize on demand. As in most oligopolies, some price variation is necessary to maintain healthy profits. Companies like Texaco and Shell should note, however, that too much variation in prices can create an unstable product market. Many companies in an oligopolistic market will use benefits given to consumers to help them reduce price differences. Texaco and Shell, for example, offer incentives middle of paper......Business Week, 3601. P. 58-64. Retrieved November 1, 2008 from EBSCOhost database. Brue, SL and McConnell, CR (2005). (16th ed.). Economics: principles, problems and policies. New York: The McGraw-Hill Companies. Carvajal. D (2005). Water, bottled water everywhere. International Herald Tribune. Retrieved November 1, 2008 from http://www.iht.com/articles/2005/02/11/business/wbwater.php Keaten, Jamey (2000) De Beers Buffs Its Image retrieved from the Internet November 1, 2008 from http: //money.cnn.com/2000/08/25/europe/diamonds/Peterson, Wallace (2008) Monopoly, Microsoft® Encarta® Online EncyclopediaRetrieved from the Internet on October 26, 2008 at http://encarta.msn.comStein, Nicholas, (2001) The De Beers Story retrieved from the Internet on October 26, 2008 at http://money.cnn.com/magazines/fortune/fortune_archive/2001/02/19/29686