Methods of corporate growth can be generalized into both internal and external growth. Internal growth is common since the existence of firms as firms can expand by increasing sales or building an extra factory for a line of production. However, as firms are seeking to grow externally, mergers and acquisitions become the main method of corporate strategies. In the mining industry, there are ongoing M&A activities, which are yet to be justified if these M&As create value for firms, and to the extent of the overall economy. The argument is that M&As usually aimed to create synergy through achieving economies of scale and/or creating some sort of market power(very rarely as there are strict antitrust laws). However, some M&As may happen due to principal-agent problem, where the managers(CEOs) have conflict of interest between maximizing shareholders' wealth and their own utilities. A good example would be the case of Xstrata's bid that happened earlier, which was disclosed to be inappropriate and therefore the M&A deal did not happen. Any opinion about the issue is welcome.