The book investigates the trends in earnings inequalities in developing countries to determine the main drivers. Particular attention is paid to extending the most conventional explanations of changes in earnings inequality, based on the relative abundance of skilled and unskilled labour, with recent theories that put the nature of tasks performed by workers in their jobs, rather than their skills, at the centre of the analysis. The latter approach has helped to explain relevant patterns recently observed in the trends in earnings inequality in the US and other industrialized countries. Developed countries have experienced a polarization in earnings and in employment, namely stronger growth in the earnings and jobs for the most and least skilled workers at the expense of those in the middle. This pattern has been attributed to differences in tasks-whether a given job is routine and can be automated or offshored-rather than skills, and has reduced employment and incomes in typical middle-class jobs in manufacturing and services. However, this narrative has been developed in the context of mature industrialized economies on the frontier of technological change that have also seen a large set of activities offshored to emergent economies. Evidence for developing countries, however, is still scarce and faces bigger challenges, both conceptual, and in terms of gathering the necessary data on earnings and task content of jobs. This book presents the main results of the UNU-WIDER project, The Changing Nature of Work and Inequality, aiming to fill this knowledge gap.