This chapter examines the key conceptual debates on inequality that were common until the end of World War II and the birth of the field of ‘development’. Two inequality-related questions have dominated development debates for decades. Firstly, does growth inevitably lead to inequality? And if so, does it matter, as long as poverty declines? The debates around these questions began in the 1950s with Simon Kuznets’ introduction of the ‘inverted-U hypothesis’, which posited that relative inequality increases, but only temporarily, in the early stages of economic growth, improving once countries reach middle-income levels. The chapter considers the politics and economics of inequality in the developing world as well as inequalities in the age of globalization. It concludes with an assessment of the World Bank’s incorporation of the goal of ‘shared prosperity’ in its discourse alongside its ongoing concern to reduce poverty.