Cities

More than 65% of the world's population are projected to live in urban areas by 2050, with major implications resource use, energy, water and sanitation, and health and well-being. At the same time urbanization can bring benefits, especially efficiency gains. SEI examines these challenges in the round to advance sustainable urbanization.

Close up of air condition vent in office ceiling.

Why indoor air quality is the next public health frontier

Perspective / "A significant blind spot remains in our national health strategy " writes Sarah West in Government Business magazine.

27 March 2026 / About Cities and Pollution

Chad launches national effort to tackle air pollution and methane

Feature / Chad has launched a national initiative to address air pollution and reduce methane and other short-lived climate pollutants

17 March 2026 / About Cities

Elderly woman walking with a cane is crossing a long crosswalk across several car lanes, an SUV is turning towards her behind her.

Mobility, power and access

Feature / From Tallinn to Bangkok, everyday journeys reveal who moves freely in the city and who faces barriers along the way.

16 March 2026 / About Behaviour and choice, Cities, Participation, Public policy and Transport

A woman stands in front of a small village clothing shop where dresses hang on the yellow wooden exterior. The woman is holding her bicycle and moving away from the store. On the forefront of the photo, different field flowers bloom.

What cities can learn from each other

Feature / Across the world, everyday journeys reveal how mobility shapes access, safety and belonging.

16 March 2026 / About Behaviour and choice, Cities, Participation, Public policy and Transport

A man and a woman are standing in the middle of the tram. The man is holding on to a support bar above with his right hand and holding his left hand around the woman's waist. The woman is holding her right hand around the man's waist.

Where movement becomes belonging

Feature / Mobility spaces are not just routes but places where social life unfolds and a sense of belonging is shaped.

16 March 2026 / About Behaviour and choice, Cities, Participation, Public policy and Transport

A person is holding a worn-looking box with different tickets in it.

The hidden cost of moving

Feature / Even when transit is free, mobility carries hidden costs in time, safety, pollution and exposure to weather.

16 March 2026 / About Behaviour and choice, Cities, Participation, Public policy and Transport

A view from above to a wooden and stone seating area surrounded by trees and bushes. Some people are sitting on chairs and browsing on their phones or chatting. Around them are many standing people who are walking, talking, taking photos, and using their phones

Spatial justice in practice

Feature / Sidewalks, crossings and street design reveal who moves with ease and who is pushed to the margins of the city.

16 March 2026 / About Behaviour and choice, Cities, Participation, Public policy and Transport

A man in black shirt with a woman in a stone wash grey jacket both wearing mask on a busy street.

Why regional cooperation is vital for better air quality in Asia and the Pacific

Perspective / In this Asian Development Bank blog, Gary Haq argues that air pollution crosses borders in Asia, so countries must cooperate regionally to address it.

12 March 2026 / About Cities

City of Mogadishu along the Indian ocean

Strengthening national air quality governance in Somalia

Project / This project strengthens Somalia’s national air quality governance through policy development and targeted capacity building

2026 - 2027 / About Cities