In 2007, Prof. Graeme Cooper of Sydney Law School in Australia was appointed to the PricewaterhouseCoopers Chair of International and European Tax Law at the European Tax College, a joint venture of Katholieke Universiteit Leuven in Belgium and Tilburg University in the Netherlands. This article is the Inaugural Address given by Prof. Cooper on 23 September 2008, as revised for publication. It explores the problem of defective anti-avoidance rules and the possibility to devise a better form of rule than those currently on display.