Transportation within the EU, as in most of the industrialized world, shows an increasing trend in CO2 emissions. This calls for measures to decrease the amount of transportation but also to increase the efficiency in the vehicle fleet. To achieve this, numerous policy measures are available, all of which targets the agents in the economy in various ways. Policy makers thus face a highly complex task. The present paper aims at providing a simple and transparent analytical model that illustrates how different policy measures address different parts of an interlinked system, which determines the composition of the future car fleet. Apart from being simple, and thereby providing an intuitive framework, the model provides important lessons for policy design, e.g., through highlighting the difference between initial responses to policies and the outcome in equilibrium both in the short and the long run. (C) 2009 Elsevier Ltd. All rights reserved.