This research explores the impact of formal mechanisms for public participation on policies regulating the provision of municipal solid waste management (MSWM) in two emerging economies: Brazil and India. It argues that although public participation is often interpreted as a means of enabling citizens to exert influence over government policies, for the benefit of society as a whole, it is in fact powerful interest groups that dominate the official participatory processes. Thus, in certain cases, rather than enhancing the political involvement of ordinary citizens, the mechanisms established to encourage public participation favour dominant economic and political forces. This research, therefore, provides a critical analysis of the concept of public participation from a theoretical interest group perspective: it identifies the main participants in these political processes, and analyses not only how and why these channels of public participation are implemented, but also who benefits from their political mechanisms. The comparative analysis of these countries is especially useful in the current context since they are both subject to immense pressure from the global market to promote economic growth, yet their ability to deal with the increasing tide of waste generated as a result, and their institutional capacity to regulate market practices, remain for the most part inadequate. Although each country has quite distinct formal decision making processes and spaces of public participation, the research reveals remarkably similar policy outcomes in the MSWM sector that is, powerful interest groups wield significant influence in both countries, albeit in specific ways. This investigation of the influence of interest groups on decision-making, therefore, furthers our understanding of how public participation works in these emerging economies, and to what extent the practices it reveals affect the quality of these countries' democracy.