The world's cities are growing, and their roadways are becoming overwhelmed. Motor vehicles are the world's leading cause of death for people between the ages of 2 and 29, killing 1.2 million people and injuring up to 50 million annually, according to the World Health Organization's update on Dec 13, 2023.
If not enough, vehicle emissions are also a major cause of air pollution, the world's second-biggest driver of chronic disease.
Cities are looking for ways to address these problems but they often face challenges. Through our involvement in the global Partnership for Healthy Cities, we have found common approaches through which city officials can join with their communities to make roads safer and healthier for everyone.
Globally, 80% of roads don't meet pedestrian safety standards and only 0.2% have bike lanes. Data from the WHO also show cities that are creating more space for pedestrians, opening bike lanes and introducing practical restrictions on motor vehicle traffic have seen the biggest improvements in road safety.
Research drawn from a variety of cities suggests this approach can have the added benefit of helping reduce people's risk of heart disease, type-2 diabetes and respiratory illness.
Despite research showing residents are happier living in more walkable neighbourhoods, efforts to improve urban mobility often hit a wall of local resistance.
Cities have even faced public protests, with communities especially divided over the prospect of restrictions on vehicle use. Yet it is possible for cities to build a broad base of public support for safe and healthy mobility, even where residents may at first oppose change.
To start, city officials should make sure they're adequately investing in data systems. Collecting accurate data on road safety and traffic patterns is critical for making evidence-based decisions and allocating resources where they'll have the most impact.
But just as importantly, data equips public officials and advocates to make a public case for changing how roadways are designed and used.
Outside the wealthiest countries, however, few cities routinely collect and analyse accurate road safety data. Weak data collection leads to an under-reporting of road crashes and casualties, making the problem harder to address.
According to research from the World Bank and others, 35% of the world's largest cities -- including 92% of the largest low- and middle-income cities -- also lack complete transportation maps, limiting their capacity to make strategic improvements to their road systems.
Today, there are more ways than ever to collect data, through mobile phones, automated sensors, ride-sharing apps and satellite imagery.
AI is even enabling the "smartification" of roadways, with real-time data helping improve safety and manage traffic flows.
Despite so, cities wanting to improve mobility should beware of relying too much on technology.
After all, personal outreach to the community is still essential. Engaging community organisations to help conduct local road-use surveys is critical for making access to roads and public transport more equitable, and determining how mobility initiatives might impact vulnerable groups.
Gathering economic data is important, too. Evidence shows pedestrians are more likely than drivers to explore local streets and shops. This evidence has aided our work to create more safe spaces for walking and biking.
Once cities have reliable data, it becomes just as important to share it effectively. Data need to be broadcast through advertising campaigns or public service announcements.
But we have found that it's equally important to share data in a targeted way, with specific constituency groups or even individual stakeholders.
In any city, there are groups that make natural allies for healthy mobility initiatives. In Guadalajara, Mexico, we worked with organisations promoting the rights of pedestrians and cyclists and the protection of the local environment.
Such groups know where they feel unsafe moving about in the city, and they contribute ideas for improvements.
We have also learned that it's important to involve business leaders as early as possible. They're an influential constituency in virtually any city, and they often fear that reducing the number of cars near their shops would mean fewer customers.
As recounted on a recent episode of the Global Health Matters podcast, efforts to restore the walkability of Bangkok's Old Town faced resistance from a restaurant owner until we showed that four out of five of their customers arrived on foot.
As businesses see foot traffic increase, they can become a powerful force for expanding walking and biking areas.
Such broad-based support has been crucial to creating Mexico's first Low Emissions Zone, a new central area of Guadalajara designed to maximise road safety, clean air and active mobility.
Ultimately, mobility is about more than getting from A to B. Navigating a city can and should be its own reward.
As cities grow, those that earn local support for safe, inclusive and active mobility will be better positioned to create the conveniences and benefits we all want from urban life.
Jesus Carlos Soto is the Director for Mobility and Transport for the Guadalajara municipal government in Mexico. Silpa Wairatpanij is a Committee Member of the Thailand Walking and Cycling Institute Foundation.