the market and can hence gain competitive advantage. A firm can either exploit an external opportunity or neutralize an external threat by using its rare and valuable resources. In this case, the firm can gain competitive advantage. When the firm's competitors discover this competitive advantage, they may respond in two ways. First, they can choose to ignore the profit gaining by the competitive advantage and continue to operate in their old ways. Second, they can choose to analyze and duplicate the competitive strategy of its rival. If there is no cost or little cost in obtaining this rare and valuable resource, the fellow firms can imitate the competitive advantage in order to gain competitive parity (firms that create the same economic value as their rivals experience competitive parity). However, sometimes it is hard for other firms to get access to the resources and imitate the innovative company's strategy. As a result, the innovative companies that implement its strategies based on costly-to-imitate and valuable resources can gain long-term competitive advantage, which ensures a company's sustained success (Hill & Jones, 1998). Hence, to sustain the competitive advantage, it is not sufficient for a firm's resources and capabilities to be valuable and rare – they should also be mostly inimitable. Forms of imitation In most cases, imitation appears in two ways, direct duplication or substitution. After observing other firms’ competitive advantage, a firm can directly imitate the resource possessed by the innovative firm. If the cost to imitate is high, the competitive advantage will be sustained. If not, the competitive advantage will be temporary. Otherwise, an imitating firm can attempt to use a substitute in order to gain similar competitive advantage of the innovative firm. Cost of imitation Cost of imitation is usually high in order to gain a competitive advantage due to the following reasons: Unique Historical Conditions – an innovative firm gains low-cost access to rare resources in a particular time and space, Causal Ambiguity – an imitating firm cannot tell the factors that lead to the competitive advantage of an innovative firm, Social Complexity – when the resources involved in gaining competitive advantage is based on interpersonal relationship, culture and other social background, Patents – a source of long-term competitive advantage certificated by authority in a few industries such as pharmaceuticals. Question of Organization Once the analyst has realized the value, rarity and imitability of the company's resources and capabilities,