Given today’s ever closer interdependence of business and IT (what we call their 'co-evolution') and the layering and increasing fragmentation of organizational structures, the corresponding architectures should assume a much greater importance for both the CIO and the CTO. This study will seek to determine the extent to which organizations are today making use of Business and IT Architectures to guide their operational, tactical and strategic decision-making. We will also make recommendations on good practice in this critical area.