Shanghai, as the most advanced mega city in China, has launched a pilot carbon emission trading scheme (SH-ETS) that is designed to achieve a compromise between the domestic context in Shanghai, and a need for national policy appeal. This paper gives an overview of the latest progress of the SH-ETS and sheds some light on the features of key design components, such as the threshold for inclusion, sector coverage, cap setting, allowance allocation and the Monitoring, Reporting and Verification (MRV) system. Based on a concern that manipulative principles and economic dynamics may lead to uncertainties and ultimately influence the emission reduction effect of the scheme, this paper conducts an evaluation of potential uncertainties, such as those caused by changes in patterns of economic growth, strategic trading activities related to the bankable allowances, carbon leakage risks and insufficient MRV capabilities. To advance the experiment to reality, this paper suggests some changes are made to the pilot, which include adjusting the allowance allocation principles to facilitate change in the domestic energy structure, improving the disclosure of emission data to guarantee information symmetry, gauging the carbon leakage risks to strengthen compliance, and introducing risk management for non-regulated players and derivatives products. (C) 2014 Elsevier Ltd. All rights reserved.