American inequality is distinctive, and the place to start is to go out to the highest level and to think a little bit about global inequality. The figure that I think has gotten the most attention on this topic in recent years has come from the work of Branko Milanovic and here it is in updated form thanks to the work of two other inequality experts Thomas Piketty and Emmanuel Saez who worked with a team of researchers to develop a very comprehensive set of measures of inequality across a wide range of political and economic systems across a wide range of nations.