In March 2000, the European Commission presented a Green Paper on greenhouse gas emissions trading within Europe, supporting implementation of a Community-wide scheme in which the design and regulation of all essential elements would be harmonized at the Community level. The present paper analyzes economic arguments used to justify such a coordinated scenario, showing these arguments to be based on misleading rhetoric about fair trade and harmonization. Diverse allocations of emissions allowances across Member States are justified in theory. In practice, too, no empirical evidence or model-based results demonstrate that an uncoordinated European trading scheme would adversely affect competitiveness to any significant extent or substantially increase industrial relocations. / Includes bibliographical references (p. 9-11). / Abstract in HTML and technical report in PDF available on the Massachusetts Institute of Technology Joint Program on the Science and Policy of Global Change website (http://mit.edu/globalchange/www/) / Supported in part by the Institut Français de l'Energie.