REHVA IAQ experts prepared a position paper on indoor air quality and climate addressing policy makers and authorities. The paper points out the potential conflicts between energy efficiency, occupancy and indoor air quality and climate. It uses the result of the HealthVent project and other EU projects, and is linked to the work of a new REHVA Task Force aiming at preparing further position papers in the future on Indoor Environment. The Task Force wants to achieve a better understanding within decision makers on IAQ issues and to have an impact on EU and national policy and regulations.