A core competency is a concept in management theory introduced by C. K. Prahalad and Gary Hamel. It can be defined as 'a harmonized combination of multiple resources and skills that distinguish a firm in the marketplace' and therefore are the foundation of companies' competitiveness. A core competency is a concept in management theory introduced by C. K. Prahalad and Gary Hamel. It can be defined as 'a harmonized combination of multiple resources and skills that distinguish a firm in the marketplace' and therefore are the foundation of companies' competitiveness. Core competencies fulfill three criteria: For example, a company's core competencies may include precision mechanics, fine optics, and micro-electronics. These help it build cameras, but may also be useful in making other products that require these competencies.