A few centuries ago, most people were poor. The Industrial Revolution and rising agricultural productivity resulted in explosive economic growth, but the ensuing rise in living standards was not evenly distributed across the world.

Early sociologists often assumed that society was progressing toward some common positive future. Many people supposed that, through modernization, nations would move from traditional forms of social organization toward forms characteristic of post–Industrial Revolution societies. Many contemporary sociologists point out that terms such as modernization and development contain an ethnocentric bias. Such modernization represents a form of cultural imperialism.

Colonialism is an alternative perspective to modernization. By the 1980s, colonialism had largely disappeared, but in many cases was replaced with neocolonialism. Immanuel Wallerstein views the global economic system as divided between nations that control wealth, and those from which capital is taken. Wallerstein advanced a world systems analysis to describe the unequal economic and political relationships in which core nations exploit periphery nations. Wallerstein's world systems analysis is the most widely used version of dependency theory, which contends that industrialized nations to continue to exploit developing nations. Globalizationis closely related to these problems. Multinational corporations have played a key role in globalization. Some believe that multinational corporations help developing nations, while critics of multinational expansion argue that they exploit local workers to maximize profits.

The gap between rich and poor nations is widening. In at least 22 nations around the world, the most affluent 10 percent of the population receives at least 40 percent of all income. Women in developing countries face significant obstacles. The UN Millennium Project aims to eliminate global poverty by 2015. Intergenerational mobility varies across countries. In developing nations, macrolevel social and economic changes often overshadow microlevel movement from one occupation to another. In large developing nations, the most socially significant mobility is the movement out of poverty, which is difficult to measure and confirm. Development may result in the modification of traditional cultural practices, but the effects on women's social standing and mobility are not necessarily positive.

Mexico is considered a semiperiphery nation. The gap between rich and poor is one of the widest in the world. The country is divided along lines of class, race, religion, gender, and age. The subordinate status of Mexico's Indians is a reflection of the nation's color hierarchy. Women comprise 45 percent of the labor force in Mexico, but are even more mired in the lowest-paying jobs than their counterparts in industrial nations. The term borderlands refers to the area of common culture along the border of Mexico and the United States. Maquiladoras are now experiencing the same challenge from global trade as U.S. manufacturing plants did. The social impact of immigration to the United States is felt throughout Mexico. The flow of remittances is second only to oil as a source of foreign revenue for Mexico.

As the impacts of globalization have spread, a movement toward ensuring universal human rights has arisen. The Universal Declaration of Human Rights was adopted by the UN in 1948. At first it was opposed by the United States. Ongoing human rights concerns include ethnic cleansing and human trafficking. Disagreements over what constitutes a violation have occurred. Efforts to protect and ensure human rights usually arise from social movements, not governments.