The main objectives of the paper are to define and analyse the importance of marketing orientation across the Greek telecommunications companies and to develop an instrument for measuring the level of marketing orientation in these companies. The marketing orientation instrument was derived from analysis of the relevant marketing literature, leading to the development of a number of research hypotheses. Specifically, MARKOR scale (Jaworski and Kohli, 1993) was used to investigate the relationship between marketing orientation, customer intelligence and innovation in Greek telecommunication market. The empirical research findings confirmed positive relationships between marketing orientation, customer intelligence acquired by those companies and innovation, but not between marketing orientation and business performance.