Idea 9 - Core competence Michael Porter and his five forces of competition looked out across the corporate battlements to survey the competitive landscape beyond. Gary Hamel and C.K. Prahalad looked within, in search of the 'core competencies' that they argued were the true source of competitive advantage. It was time, they said, for top executives to rethink the concept of the corporation. Hamel and Prahalad were reacting against the decentralized business portfolio strategy being followed by many large corporations. Instead of a portfolio of businesses, housed in more or less standalone 'strategic business units' (SBUs), companies should think of themselves as a portfolio of competences, they urged in a highly influential 1990 Harvard Business Review article, 'The core competence of the corporation'. The industrial backdrop against which they were writing was one in which Western companies had begun to steady themselves against the low cost and high