In 1975, only three cities worldwide topped 10 million. Today there are at least 35 such megacities, including Kolkata, shown above, home to an estimated 15 million. (Steve Raymer/The Washington Post)

More than 75 percent of the globe will live in cities by the year 2050. This week in Quito, Ecuador, Habitat III, the United Nations’ third Conference on Housing and Sustainable Urban Development, convenes to plan for continued global urbanization.

One of the conference goals is ratifying the New Urban Agenda, which will “set global standards of achievement in sustainable urban development, rethinking the way we build, manage and live in cities.”

As more than 30,000 mayors, policymakers and urban planners in Quito discuss these issues, what can political scientists contribute to these debates? Here are four areas where political science research can help improve our understanding of urban dynamics.

1. Sources of inequalities

Habitat III will address the need to make cities more inclusive so that all residents, rich and poor, have a political voice as well as economic opportunities. With the roots and mechanisms of inequality often distinctly political, political science research can help chart policies to reduce inequality in the cities of the future.

For example, Sean Fox looks at how colonial-era investments and planning contributed to the growth of slums in modern-day Africa. Jacqueline Klopp explains how the modern political economy left the poor out of the planning process in Nairobi. Other researchers compare cities in India and East Africa to see how political and social pressures affect government efforts to improve infrastructure quality.

Political scientists also look at how urban residents gain a louder political voice and the ability to shape their communities. In Brazil, Maureen Donaghy investigates how the participation of housing councils contributed to more equitable and affordable housing outcomes. Alisha Holland introduces the idea of forbearance to explain why governments decide not to enforce laws against street vendors in many South American cities. Governments allow illegal vending as a form of informal social welfare, and the poor use their votes as a way to demand these benefits.

2. The politics of infrastructure

Habitat III highlights the need for better urban infrastructure, but the politicization of public services can leave large portions of the population without adequate access to public goods. In urban Mexico, citizen water boards lost their autonomy, eventually becoming partisan-controlled. In Argentine cities, multinational corporations performed poorly when privatizing the water and sanitation sectors because they did not understand the politics on the ground.

In some Indian slums, however, local party leaders successfully brought infrastructure improvements to marginalized communities. In addition, neighborhood organizations in Taipei evolved to empower urban communities to gain more access to welfare programs. And citizens’ voluntary compliance is crucial for local governments’ ability to tax in urban Nigeria, which could allow for more spending on infrastructure in the future.

3. The informal economy

The New Urban Agenda recognizes the importance of the informal economy — the unregulated, off-the-books activities that sustain perhaps half of the world’s working population — but also seeks to “support a sustainable transition to the formal economy.” A focus on the informal economy, informal politics and growth of informal settlements are welcome additions to U.N. sustainable development goals.

Scholars of comparative politics examine the relationship between formal and informal politics and economies, using fieldwork to uncover the actors and institutions working in these spaces.

In an analysis of Nigeria’s open-air markets, Shelby Grossman investigates how private market organizations enforce contracts when they perceive a threat of interference by politicians. The credibility of government policies, sources of legitimacy and state “infrastructural power” contribute to differences in regulation of the informal transport sector in Uganda and Rwanda. And my research on urban Ghana suggests that informal norms of parenthood, entrepreneurship, religion and friendship constrain politicians and bureaucrats from investing in policies that help all Ghanaians.

4. Human networks

Habitat III focuses specifically on migration, emphasizing how cities should offer all residents equal rights and services, instead of having migrants live in segregated areas with few opportunities or legal rights.

Cities are where many new migrants establish homes, demand citizenship rights, and access resources and public goods. But ethnic, class and political conflicts often emerge, as Adrienne LeBas documents in urban Kenya and Nigeria, and Noah Nathan highlights in urban Ghana. And Loren Landau looks at how new arrivals in African cities become integrated in local societies and local politics.

Network analysis” in political science looks at the effect of social, economic and political connections. Focusing on the networks of urban communities, including migrant populations’ interactions in informal markets, is one way to understand the roots of cooperation and competition, as this study of Indian cities suggests.

Political science and sustainable urban development

Most of the policymaking and theorizing on urban development focuses on global markets, formal institutional reforms and urban planning. But political scientists can inform these debates through the use of field research, as well as systematic analysis on urban governance and the politics of resource distribution.

Eleanora Pasotti’s study of Bogota, Naples and Chicago, for instance, looks at how cities suffering from decades of poor government, entrenched patronage and social conflict transition to new governance.

In a way, sustainable urban development, advocated by Habitat III, is a new brand for cities and their mayors to adopt as a way to confront the most pressing issues of our times. Political scientists can play an important role in informing this brand and best practices in sustainable urban development. Understanding how politics play out in our cities should be part of any analysis of sustainable urban development.

Jeffrey W. Paller is an assistant professor of politics at University of San Francisco and curates the weekly news bulletin This Week in Africa. Follow him on Twitter @JWPaller.