Harvard Business School's Michael E. Porter introduced the concept of a value chain in his book, "Competitive Advantage: Creating and Sustaining Superior Performance," in 1985. In his book he writes:
"Competitive advantage cannot be understood by looking at a firm as a whole," Porter wrote. "It stems from the many discrete activities a firm performs in designing, producing, marketing, delivering and supporting its product. Each of these activities can contribute to a firm's relative cost position and create a basis for differentiation."