The Klaus Vogel Lecture, given in the memory of Prof. Dr Klaus Vogel who passed away in December 2007, is being continued by the Institute for Austrian and International Tax Law (WU) in Vienna. This year's lecture was given by Jacques Sasseville of the OECD at the WU on 24 October 2008. Frank Engelen (University of Leiden and PricewaterhouseCoopers Netherlands) commented on the lecture. This article is the 2008 Klaus Vogel Lecture given by Jacques Sasseville, as revised for publication. It deals with a difficult issue that arises as a consequence of "the new approach of the OECD" to conflicts of qualification.