The gap between rich and poor has widened not only in developing countries and emerging economies, but also in developed countries, and even in traditionally egalitarian nations. In other words, the reason for inequality has regional and national as well as historical, policy and institutional origins.
Inequality has been growing for decades, but this trend has intensified in the beginning of this century. Today inequalities are present in almost every area of development.
There is strong evidence that countries with more inequality systematically have less equality of opportunity. In most cases, inequality persists and even takes root in different dimensions of development. In the USA, social mobility has become a casualty of income inequality.