The United Nations General Assembly has designated October 31st of every year as "World Cities Day." It was first celebrated in 2014 to raise international awareness about the trends of urbanization. As current global urban growth brings challenges, including problems from increasing urban populations—especially environmental issues such as pollution and unsustainable resource use—World Cities Day is an important opportunity to promote international cooperation and encourage all sectors to participate in developing cities in all dimensions (economic, social, and environmental) to create sustainable cities and improve people's quality of life.

For 2025, World Cities Day will be celebrated under the theme "people-centred smart cities." This theme focuses on the role of technology and artificial intelligence (AI) in improving urban life and helping cities recover from crises or various challenges, whether they be environmental problems, natural disasters, climate change, or economic and social challenges. It emphasizes "people" as the heart of change and sustainable urban development.

According to data from UN-Habitat, the global urban population is projected to increase significantly from 3.5 billion people today to 6.2 billion by 2050. The causes of this migration to cities include conflict, environmental degradation, climate change, poverty, and spatial inequality, which push people to relocate to urban areas seeking safety, shelter, basic services, and better livelihood opportunities.

The Thailand Environment Institute (TEI), as an organization committed to working collaboratively towards sustainable development, has played a key role in promoting public awareness of the link between "the environment and urban development." This is done through knowledge exchange, as well as driving the development of green cities and supporting climate change adaptation through projects and collaborations with the public sector, private sector, and local communities. Examples include promoting circular economy approaches, clean energy use, integrated urban waste management, increasing green spaces, aiming to reduce greenhouse gas emissions, and promoting the development of smart cities that use technology for effective urban planning and management. These approaches will help cities not only grow economically and socially but also protect the environment, adapt to climate change, create a conducive living environment, and develop into sustainable and livable cities in the long term.

Urban development is therefore not just about creating technology or infrastructure, but about creating a balance between "people and the environment" to grow together sustainably.

Source: The website of the United Nations Human Settlements Programme (UN-Habitat)