Are international organizations a positive force in improving good governance and reducing corruption? International organizations have traditionally been perceived as a positive force in international politics. This paper suggests that the effect of interaction with international organizations on quality of government (QoG) norms may depend on the type of system international organizations promote. In a study on the role of international organizations as constructers, supervisors and catalysers of the carbon market through the clean development mechanism (CDM), the paper shows that there are at least three major explanations why international organizations may promote bad rather than good government norms: leadership explanations, market logic explanation and informational explanations. The paper thereby shows the benefits of moving beyond descriptions of system level features, such as inbuilt transparency mechanisms, to also study the effect that systems have on participants involved. The analysis has implications for our understanding of the influence of international organizations in an area often ignored by good governance scholars: how and in what way international organizations influence quality of government through their important and growing role in the implementation of international environmental agreements