This assignment will address how a company can gain a competitive advantage over similar companies in the same market using sources such as cost advantage and differentiation. The value chain model made by Porter will also be discussed and this assignment will explain what the model was actually designed for. Furthermore, it will be explained how a company can use competitive advantage methods across the various stages of Porter's value chain to help it maintain and increase the company's competitiveness, and this will be done by evaluating the company's operations and locating exactly where it is possible to obtain any competitive advantage. Finally, Porter's value chain presents 9 activities that can be identified as primary or support activities and what will then be explained will be how these primary and support activities can add value to a company and whether support activities can or less be considered more or less important than a primary activity. Many suggest that there are two ways in which a company can gain a competitive advantage; this occurs through cost advantage or differentiation. Porter (2004, p.64) argues that cost advantage occurs when “a firm achieves a lower cumulative cost in carrying out valuable activities than its competitors”. A good example of this would be ASDA in the food retail sector. ASDA (ASDA beats its full-year sales and profit plan, 2009), known for its "commitment to keeping prices low every day", is a cost-leading competitor in the produce retailing industry food and said it beat its “full-year sales and profit plan” for the fourth consecutive quarter in 2009, introducing a “significant cost reduction program…… half of the document……l Group (2008) Annual report 2008: Our key strengths. [Online] Available at: http://www.homeretailgroup.com/ar/2008/review/keystrengths/p2.shtml (Accessed: 11/19/2011) Johnson, G., Scholes, K. (2002) Exploring Corporate Strategy: text and cases. 6th ed. Harlow: Pearson Education Limited.McGeary, R. (2011) Anatomy of Market Research [Online] Available at: http://www.remnet.com/porter.html (Accessed: 14/11/2011)Millar, V ., Porter, M. (1985) "How information gives you a competitive advantage", Harvard Business Review pp. 18-36. [Online] Available at: http://zaphod.mindlab.umd.edu/docSeminar/pdfs/Porter85.pdf (Accessed: 11/17/2011) Needle, D. (2000) Business in Context: An Introduction to business and its environment. Third edition. London: Thomson LearningPorter, M. (2004) Competitive Advantage: Creating and Sustaining Superior Performance. New York: FREE PRESS.