Physical interventions to lower speeds are among the most effective at reducing deaths and serious injuries – and help cities chart a more sustainable future.

WASHINGTON, DC (May 20, 2021) — Speed is one of the main risk factors in road crashes and is a leading contributor to death and serious injury. Globally, more than 1.35 million people die from road crashes every year – and rising. Things can be different though; we know what works.

Higher speeds are associated with a significantly higher crash risk: even small increases in speed significantly increase the probability of death or injury. Traffic crashes are now a leading cause of death worldwide, and the number one cause of death and serious injury for young people aged 5 to 29.

To help address the collective impact of speed as a contributor to crash risks, the World Resources Institute and World Bank’s Global Road Safety Facility (GRSF) launched a new Low-Speed Zone Guide today, supported by Bloomberg Philanthropies, which helps empower communities and decision-makers to plan, design and implement effective interventions.

“Establishing lower speeds helps achieve not only road safety goals, but climate and social equity goals,” said Claudia Adriazola-Steil, Acting Director of Urban Mobility and Director of Health & Road Safety at WRI Ross Center for Sustainable Cities. “Lower speeds create safer streets, more livable neighborhoods and healthier, more sustainable environments – environments that encourage walking and cycling over car dependency.”

As the COVID-19 pandemic has significantly altered urban landscapes around the world, cities are facing new challenges and there is increased urgency for improved road safety. Many cities are now tasked with protecting more vulnerable users in addition to creating safe public spaces that will enable economic recovery and allow residents to enjoy the outdoors. At the same time, walking and cycling are among the most sustainable ways to get around cities – but not if they are extremely dangerous.

Low-speed zones are therefore not only key to improving safety by reducing fatalities and injuries, but also reap a variety of other benefits, ranging from better air quality, to economic recovery to long-term sustainability.

But not all low-speed zones are equally effective. To maximize safety and other benefits, low-speed zones need to be well-planned, well-designed and well-built. Physical traffic-calming measures – not just speed limit changes – and target speeds of 30 kilometers/hour or lower have the greatest proven safety benefits.

Key considerations for implementation include stakeholder engagement, site selection, enforcement, and the adaptation of basic principles of design to the local context. Monitoring and evaluation are also critical for understanding how successful a low-speed zone is in achieving goals and objectives. Ideally, evaluation should include consideration of impacts on commerce (if relevant) as well as safety and other public goods.

“Lower speeds can save countless lives and create healthier, more livable communities,” said Pablo Fajnzylber, Acting Vice President for Infrastructure at the World Bank. “The World Bank is strongly committed to road safety and pleased to partner with WRI on this new manual, which provides concrete guidance on the effective implementation of low-speed zones and will help build community and decision-maker support for these environments.”

Download the Low-Speed Zone Guide from


About World Resources Institute 

WRI is a global research organization that spans more than 60 countries, with international offices in Brazil, China, India, Indonesia, Mexico and the United States, regional offices in Ethiopia (for Africa) and the Netherlands (for Europe), and program offices in the Democratic Republic of Congo, Turkey and the United Kingdom. Our more than 1,000 experts and staff turn big ideas into action at the nexus of environment, economic opportunity and human well-being. More information at

About WRI Ross Center for Sustainable Cities 

WRI Ross Center for Sustainable Cities is the World Resources Institute’s program dedicated to shaping a future where cities work better for everyone. It enables more connected, compact and coordinated cities. The Center expands the transport and urban development expertise of the EMBARQ network to catalyze innovative solutions in other sectors, including air quality, water, buildings, land use and energy. It combines the research excellence of WRI with two decades of on-the-ground impact through a network of more than 350 experts working from Brazil, China, Ethiopia, India, Mexico, Turkey and the United States to make cities around the world better places to live. More information at