The influence of interest groups in politics poses potential threats to democracy. The challenges of collective action predict that the groups most likely to be represented will have concentrated economic interests or intensely held beliefs, resulting in policies at odds with general public opinion. While such biases in representation are clear in theory, there is scant systematic evidence of disproportionate influence over government by a subset of interest groups. Further, social scientists know little about the degree of correspondence between the political preferences of interest groups and those of the public. Agendas and Interest Groups is a comparative project that for the first time will address concerns about the role of interest group influence by focusing attention on policy agendas and analyzing the circumstances under which specific types of groups and citizens find their issues represented before government. To estimate the degree of congruence between the concerns of citizens and the policy agendas of interest groups and government, we will interview representatives from a random sample of 100 interest groups in each of our four countries, survey the general public in each country about their policy wishes, and track three specific issues in each of three policy areas in each country. In mapping each country’s public, group, and government agendas, we aim to address normatively important questions about the extent and causes of inequalities in representation.