exerted by point R cancel each other out. In the same book, Tellier solved that problem for the first time in the triangle case, and he reinterpreted spatial economics theory, especially, the theory of land rent, in the light of the concepts of attractive and repulsive forces stemming from the attraction-repulsion problem. That problem was later further analyzed by mathematicians like Chen, Hansen, Jaumard and Tuy (1992), and Jalal and Krarup (2003). The attraction-repulsion problem is seen by Ottaviano and Thisse (2005) as a prelude to the New Economic Geography that developed in the 1990s, and earned Paul Krugman a Nobel Memorial Prize in Economic Sciences in 2008. Agglomeration and deagglomeration Agglomeration is the phenomenon of spatial clustering, or a concentration of firms in a relatively small area. The clustering and linkages allow individual firms to enjoy both internal and external economies. Auxiliary industries, specialized machines or services used only occasionally by larger firms, tend to be located in agglomeration areas, not just to lower costs but to serve the bigger populations. Deglomeration occurs when companies and services leave because of the diseconomies of industries’ excessive concentration. Firms who can achieve economies by increasing their scale of industrial activities benefit from agglomeration. However, after reaching an optimal size, local facilities may become over-taxed, leading to an offset of initial advantages and increase in prime cost. Then the force of agglomeration may eventually be replaced by other forces which promote deglomeration. Globalization Similarly, industrial activity is considered a secondary economic activity, and is also discussed as manufacturing. Industrial activity can be broken down further to include the following activities: processing, the creation of intermediate parts, final assembly. Today with multinational corporations, the three activities listed above may occur outside MDCs. Weber's theory can explain some of the causes for current movement, yet such discussion did not come from Weber himself. Weber found industrial activity the least expensive to produce. Least cost location then implies marketing the product at the least cost to the consumer, much like retailers attempt to obtain large market shares today. Economically, it is explained as one way to make a profit; creating the cheapest product for the consumer market leads to greater volume of sales and hence, greater profits. Therefore, companies that do not take the time to locate the cheapest inputs or the largest markets would not succeed, since their product costs more to produce and