This course gives an introduction to social choice theory. Social choice theory explores the role that decision making mechanisms, such as voting mechanisms, play in mapping preferences into outcomes. A source of interest in this study is the problems that can arise with decision making mechanisms, such that outcomes fail to reflect the preferences of the group. A key cause of these problems is insufficient information: we assume that our decision-making mechanisms will use specific information, but, in fact, they do not. Indeed, many of our mechanisms exclude crucial information elements from the process, making lack of representation more likely. This class will explore the basics of these problems, integrating the role of information into the analysis.