Income inequality is rising. A quarter of a century ago, the average disposable income of the richest 10% in OECD countries was around seven times higher than that of the poorest 10%; today, it's around 9½ times higher. Why does this matter? Many fear this widening gap is hurting individuals, societies and even economies. This book explores income inequality across five main headings. It starts by explaining some key terms in the inequality debate. It then examines recent trends and explains why income inequality varies between countries. Next it looks at why income gaps are growing and, in particular, at the rise of the 1%. It then looks at the consequences, including research that suggests widening inequality could hurt economic growth. Finally, it examines policies for addressing inequality and making economies more inclusive.

This report provides evidence of a fairly generalised increase in income inequality over the past two decades across OECD countries, but the timing, intensity and causes of the increase differ from what is typically suggested in the media.

We posit that the relationship between income inequality and economic growth is mediated by the level of equality of opportunity, which we identify with intergenerational mobility. In economies characterized by intergenerational rigidities, an increase in income inequality has persistent effects—for example by hindering human capital accumulation— thereby retarding future growth disproportionately. We use several recently developed internationally comparable measures of intergenerational mobility to confirm that the negative impact of income inequality on growth is higher the lower is intergenerational mobility. Our results suggest that omitting intergenerational mobility leads to misspecification, shedding light on why the empirical literature on income inequality and growth has been so inconclusive.

This paper analyzes the extent of income inequality from a global perspective, its drivers, and what to do about it. The drivers of inequality vary widely amongst countries, with some common drivers being the skill premium associated with technical change and globalization, weakening protection for labor, and lack of financial inclusion in developing countries. We find that increasing the income share of the poor and the middle class actually increases growth while a rising income share of the top 20 percent results in lower growth—that is, when the rich get richer, benefits do not trickle down. This suggests that policies need to be country specific but should focus on raising the income share of the poor, and ensuring there is no hollowing out of the middle class. To tackle inequality, financial inclusion is imperative in emerging and developing countries while in advanced economies, policies should focus on raising human capital and skills and making tax systems more progressive.

This state-of-the-art volume presents comparative, empirical research on a topic that has long preoccupied scholars, politicians, and everyday citizens: economic inequality. While income and wealth inequality across all populations is the primary focus, the contributions to this book pay special attention to the middle class, a segment often not addressed in inequality literature. Written by leading scholars in the field of economic inequality, all 17 chapters draw on microdata from the databases of LIS, an esteemed cross-national data center based in Luxembourg. Using LIS data to structure a comparative approach, the contributors paint a complex portrait of inequality across affluent countries at the beginning of the 21st century. The volume also trail-blazes new research into inequality in countries newly entering the LIS databases, including Japan, Iceland, India, and South Africa.

The contributors argue that there need not be a trade-off between growth and equity in the long run. However, attempts by government to influence income distribution through large-scale tax and transfer programs can have a negative impact on growth. The contrast is vivid. While the majority of people in the industrial world and some in the developing world enjoy unprecedented affluence, a far greater number of people in the low-income countries live in abject poverty. Although several developing countries are achieving rapid economic growth and poverty reduction, most formerly centrally planned countries are struggling to implement market-oriented reforms in the midst of economic deterioration and rising poverty. The paramount importance of reducing poverty worldwide is forcing economists and policymakers to look at how income distribution and economic growth interact. The essays in this volume grew out of a 1995 conference sponsored by the International Monetary Fund. The contributors are scholars and policymakers from academic institutions, governments, and international organizations. The questions discussed include: How does income distribution interact with economic growth in the short run and the long run? To what extent can government use transfer programs to increase the incomes of the poor? How can government use social programs to help the poor increase their income-earning capacity? Does distributional inequality create an obstacle to long-term poverty reduction? Alternatively, is distributional inequality a necessary means of achieving economic growth? Generally, the contributors agree that there need not be a trade-off between growth and equity in the long run. However, attempts by government to influence income distribution through large-scale tax and transfer programs can have a negative impact on growth.

Eight papers, both theoretical and applied, on the concept of equality of opportunity which says that a society should guarantee its members equal access to advantage regardless of their circumstances, while holding them responsible for turning that access into actual advantage by the application of effort.