By now, inequality has assumed centre stage in many international debates. For example, whilst the headline focus of the MDGs until 2015 was on halving extreme poverty, the 2030 Agenda for Sustainable Development added an SDG on inequality reduction. This shift in policy focus has implications for global governance. This chapter discusses key measures and trends of global inequality, investigates the importance of inequality for other important aspects of the global economy, and sketches some of the implications for global governance. For space limitations, we focus on global income inequality. [...].This chapter discusses inequality measures and trends in income inequality and wealth. It also distinguishes national and global inequalilty. The chapter covers income and wealth and their respective trends before sketching out key implications for global governance.