Smart sustainable cities

Despite occupying just 1.7% of the Earth's surface, cities are home to 57% of the global population and contribute to 70-80% of anthropogenic air pollution^[1]​​​​. Rapid urbanization amplifies challenges such as social inequality, traffic congestion, and environmental degradation − all of which directly affect public health and quality of life.

Yet, these challenges present an opportunity for transformation. By harnessing digital technologies, governments and municipalities can reimagine cities as smarter, more sustainable spaces that put people at the centre of development.

A smart sustainable city is an innovative urban environment that leverages information and communication technologies (ICTs) and other tools to:

• Enhance quality of life for residents,
• Optimize urban operations and services,
• Boost competitiveness, and
• Ensure that cities meet the economic, social, environmental, and cultural needs of both present and future generations.

Through a people-centred and tech-enabled approach, cities can become catalysts for positive change, fostering sustainable growth and resilience in the face of global challenges.​

CHALLENGES OF URBANIZATION AND DIGITAL TRANSFORMATION

Cities around the globe are grappling with the rapid pace of urbanization and digital transformation, which present a complex web of challenges.

• Strained infrastructure and services: The influx of people into urban areas is overwhelming housing, transportation, and public services. Energy, water, and waste systems are under significant pressure, leading to unsustainable resource consumption and operational inefficiencies.
• Connectivity demands: The explosion of Internet users, mobile devices, and Internet-of-things (IoT) technologies has created an urgent need for robust connectivity, network capacity, and efficient data management systems. Ensuring interoperability and addressing cybersecurity risks have become critical tasks in this digital age.
• Environmental stress: Urban areas account for a substantial share of greenhouse gas emissions and pollution. Rising temperatures, exacerbated by climate change, are projected to expose over 2 billion urban dwellers to a 0.5°C temperature increase by 2040, intensifying urban heat island effects and further straining resources.
• Mobility and congestion: Overburdened transport systems and traffic congestion reduce the quality of urban living and economic productivity.
• Digital inequities: Unequal access to digital technologies and services creates gaps in connectivity that perpetuate social inequalities. This digital divide leaves some communities disconnected, unable to benefit from advancements in smart urban solutions.
• Security and inclusivity: The expansion of digital services introduces concerns about privacy, cybersecurity, and the challenge of ensuring equitable access for all urban residents.

As urban populations and digital infrastructures continue to grow, cities face a critical juncture: without innovative, people-centred solutions, these challenges risk undermining their sustainability, resilience, and quality of life.

TRANSFORMATIVE SOLUTIONS FOR SMARTER, SUSTAINABLE CITIES

Digital technologies offer powerful tools to address the multifaceted challenges faced by cities, paving the way for smarter, more efficient, and sustainable urban ecosystems. Key innovations include:

• Internet of things (IoT): Connecting devices across urban systems enables real-time monitoring and optimization of services such as traffic management, energy distribution, and public safety.
• Digital twins and the citiverse: Immersive virtual environments and simulations support city planning, predictive maintenance, and operational efficiency, offering cities the ability to innovate in a risk-free digital space.
• Artificial intelligence (AI): Analysing vast datasets, AI enhances decision-making, automates processes, and drives improvements in municipal services.

These technologies empower cities to drive innovation across various sectors:

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• ​ Transportation: Smart systems improve traffic flow, enhance public transit, and reduce emissions, leading to more efficient and sustainable mobility solutions.
• Agriculture: Precision farming techniques optimize water usage, monitor crop health, and boost yields, contributing to food security.
• Healthcare: Telemedicine, predictive health analytics, and efficient hospital management systems revolutionize urban healthcare delivery.
• Energy: Smart grids, renewable energy integration, and energy-efficient practices reduce consumption and promote sustainability.
• Public administration: Digital platforms streamline citizen services, enhance transparency, and strengthen governance.
• Manufacturing: Smart factories and optimized supply chains increase productivity while reducing waste and environmental impact.

By integrating these advanced solutions, cities can:

• Reduce their environmental footprint;
• Enhance quality of life for residents, and
• Build resilient, inclusive urban ecosystems capable of thriving in the face of future challenges.

These innovations are key to creating smart sustainable cities that prioritize people, the planet, and prosperity.​

The International Telecommunication Union (ITU) is a driving force behind the global transition to smart sustainable cities, fostering collaboration, capacity building, policy development, and awareness-raising to ensure a people-centered approach to urban transformation.

Setting standards for the future of cities and communities

Through ​Study Group 20 (SG20) of the ITU Standardization Sector (ITU-T), ITU develops cutting-edge standards, guidelines, reports, and methodologies for the Internet of things (IoT), digital twins, and smart sustainable cities and communities (SSC&C). These efforts aim to accelerate digital transformation in both urban and rural areas.

Key areas of focus include:

• Technological aspects: Defining requirements, architectures, functionalities, and protocols to enable IoT, digital twins, and SSC&C solutions that meet global needs.
• City services and applications: Creating innovative solutions for critical sectors such as transportation, healthcare, energy, and beyond.
• Frameworks and impact assessment: Developing performance measurement frameworks and methodologies to evaluate the success and impact of smart city initiatives.
• Interoperability: Ensuring seamless integration and collaboration between diverse technologies and services to foster cohesive and scalable urban ecosystems.
• Open-source solutions: Promoting transparency and collaboration through open-source platforms, enabling cost-effective and adaptable smart city technologies.

Enabling sustainable urban futures

By establishing robust, secure, and sustainable systems, ITU ensures that cities worldwide are equipped to tackle modern challenges, from environmental degradation to social inequality. These initiatives enhance the quality of life, support sustainable development, and help create inclusive urban spaces for present and future generations.

Through its leadership and expertise, ITU remains a key partner for cities and communities striving to leverage technology for a smarter, more sustainable future.

Global collaboration and policy support

The United for Smart Sustainable Cities (U4SSC) initiative, backed by 19 UN agencies, serves as a vital platform for fostering global cooperation in developing smart city policies. It helps cities benchmark progress, share best practices, and align their efforts with the UN Sustainable Development Goals (SDGs).

Key features of the U4SSC initiative include:

• ​ Thematic groups: U4SSC thematic groups provide actionable insights by developing action plans, technical specifications, case studies, and guidelines. They address key topics such as AI in cities, people-centred digital transformation, digital public infrastructure, and future foresight for cities.
• Country hubs: Located in Austria and Ghana, country hubs foster collaboration between public and private sectors, accelerating digital transformation in cities and communities.
• Key performance indicators (KPIs): Over 200 cities globally have adopted U4SSC KPIs to measure their smartness and sustainability. Recent participants, including Quito (Ecuador), Anyang (Republic of Korea), and Kyebi (Ghana), underscore the initiative's expanding global reach and impact.

Capacity building and raising awareness

ITU empowers cities with the tools, knowledge, and resources to embrace digital transformation and foster sustainable urban development.

• Digital transformation dialogues: With over 60 sessions held to date, these dialogues disseminate critical knowledge and promote understanding of emerging technologies and technical standards, offering a platform for cities to stay ahead of the curve.
• Digital transformation resources hub: ITU's extensive resource library covers topics including smart cities, AI, blockchain, and the metaverse, providing comprehensive guidance for cities navigating their digital transformation journeys.
• UN toolkit on digital transformation for people-centered cities and communities: This toolkit helps cities strategize and plan for digital transformation, promoting sustainable, inclusive, and resilient urban development while improving the quality of life for residents.

Through initiatives like U4SSC and targeted capacity-building efforts, ITU continues to lead global efforts in driving smart, inclusive, and sustainable cities for the future. 

[1] ​UN Habitat, World Cities Report 2024​

Last update: April 2025​​