Made these first comments, it is inferred that ' ' cluster it is an agglomeration of considerable size of firms in an area especially delimited with clearly specialization profile and in which the commerce and the specialization interfirmas is substancial.' ' (Altenburg and Meyer-Satamer apud SUZIGAN, 1999:04). As it was said before, beyond this specialization ' can also have the factor; ' cooperao' ' in cluster, in case that where the enterprise relations happen of interarticulada form, by means of ' ' action conjunta' ' of economic agents social, existing intense competition between the local companies at the same time where the firms collaborate ones with the others, forming an innovative environment where if they develop positive synergies through the reciprocal confidence between entrepreneurs, cooperation interfirmas, mutual learning and collective innovations. In the mat of this reasoning, SCHMITZ (1997: 172) detached importnciatanto of ' ' economiasexternas' ' comoda ' ' aoconjunta dasempresas' ' , comoforma to elucidate the success reached for the PME' s pertaining to an industrial district: ' ' Such action can be of two types: sole proprietorships cooperating (for example, sharing equipment or developing a new product), or groups of firms congregating forces in enterprise associations, trusts of producers and assemelhados' ' . The conjugao of these two factors (external economies and joint action) took SCHMITZ (1997: 173) to add a new and valuable concept in the modern literature of clusters, that is, the concept of ' ' efficiency coletiva' ' which is defined as ' ' the competitive advantage derivative of the local external economies and action conjunta.' ' of the companies, workers and excessively socioeconmicos agents. (SCHMITZ, 1997:173). Outrossim, PORTER (1999: 225) admit that many of the competitive advantages of clusters depend on ' ' economies externas' ' or of ' ' extravasamentos' ' (collateral effect between some types of companies and sectors). Destarte, them aglomeradosdesempenham an important paper in the competition and brings excellent implications for the companies, governments and other institutions of the economy in the current scene of the globalizado world. .