Inequality is an economic, sociological, legal, political, moral, mathematical and statistical fact. It can be understood and judged from many different perspectives. This class will explore some of those perspectives with particular emphasis on the economic angles, but allowing students to bring their knowledge, interests and concerns to bear in research and presentations. This class will devote time to understanding how inequality is measured and what the evidence shows, for countries and regions around the world. We shall explore the political and moral dimensions, the question of inequalities by race and gender, the relationship between inequality and instability in economic growth, and the structural relationship between inequality and phases of economic development. The topic is vast and our approach will be eclectic. There will be some emphasis on the element I have worked on most, which is the clear evaluation of available evidence, especially related to measurement of income inequalities, the problem of inferring measures from diverse and uneven data sources, uncovering relationships and patterns of change in inequality at the national, continental and global levels, and drawing reasonable inferences from often-murky information. While this is primarily a class on economic inequality, students interested in other dimensions such as legal and social inequalities and inequalities of opportunity and access to services are welcome and encouraged to explore those issues. There will be attention to the issues raised by inequalities in the United States, and those in other parts of the world, as well as inequalities between countries. This is a seminar. The class will meet to discuss the main features of the readings and then to explore the interests and research of each student. Class discussion should be open and freewheeling. For the readings up to Spring Break, each student should submit, each week, a one-page memorandum of comments, reactions and questions, based on the readings, which is due just in advance of the class. I will read these, make brief comments and return them; they will not be graded, though submission and quality will be noted. For the second half of the course, we will organize students (mostly) into groups with (somewhat) similar interests, and each student will prepare a presentation, followed by a paper. In some cases joint work may be organized; I have found that organizing cooperation between students is an effective way to ensure a high quality of work, and that the experience of working together is often highly rewarding, as well as reducing the competitive element in the exercise. Length is not a major criterion for a good paper; the important thing is to turn in good work that describes and analyzes a relevant problem in a sensible and well-written way.