It’s no surprise to see self-driving vehicles cruising around the 2017 Consumer Electronics Show. A large parking lot has been set aside for displays and demonstrations of autonomous vehicles by manufacturers and suppliers.

But this year several exhibitors are showcasing related technologies that allow cars to communicate wirelessly with each other, as well as with smart equipment embedded in traffic lights, road signs, and other parts of the road infrastructure. Before the show opened, we got several demonstrations of how it works.

When cars talk to each other, it’s known as vehicle-to-vehicle (V2V) communications. When they communicate with the roadway or traffic signals, it’s known as vehicle-to-infrastructure (V2I). Collectively, the technology is known as V2X.

The hope for V2X is that once cars and infrastructure are all equipped with compatible wireless technologies, the real-time, automatic communication among millions of vehicles will improve safety and convenience while reducing traffic and fuel consumption.

Because so few vehicles currently have V2X technology installed, the benefits to average drivers are largely theoretical. In our demo, we rode in cars equipped with systems by industry suppliers Delphi and Savari that warned of imminent collision with other connected cars during lane merges, emergency stops, and at intersections.

We also saw how these vehicles could warn a driver that he or she was approaching a construction site, or about to run a red light, or even help adjust speed to cruise through a green.

In our demos, alerts showed up onscreen, but they could also be delivered by vibrating the driver’s seat or through audible alerts. How these systems are deployed will primarily be up to automakers.

These V2X systems can work in tandem with other advanced safety systems, such as autonomous emergency braking technology that uses camera, radar, or lidar to detect and prevent an accident. According to Ravi Puvvala, CEO of Savari, V2X systems offer benefits that other systems can’t.

“V2X systems are non-line of sight, and they work regardless of weather,” Puvvala says. The systems “will all have to coexist with each other,” he adds.

The Department of Transportation has been researching V2X for decades, but the idea has gained urgency in the past few months. In December, the DOT proposed a rule that would require automakers to install the technology in new cars that would share information about each car’s speed, location, and direction, as well as other data.

But automakers don’t seem to be waiting for the mandate to become official. Many of Audi’s 2017 A4, Q7, and Allroad models can interact with smart stoplights, and GM has promised that the V2V technology will be embedded in the 2017 Cadillac CTS.

States and cities are moving aggressively, too. New York, Wyoming, Michigan, and Nevada are among the early adopters, building smart stoplights and roads that can monitor weather conditions. Las Vegas currently has outfitted several of its intersections with V2I installations.

At CES, we spoke with Dan Langford of the Nevada Center for Advanced Mobility, a nonprofit that helps coordinate V2X efforts in Nevada. He pointed out that, as self-driving technology evolves rapidly, states and cities have an opportunity to innovate the roads and highways.

“Infrastructure is something we can have an influence on,” he says. “The low-hanging fruit for us is traffic management—optimizing flows by connecting directly with vehicles.”

Even though V2X technology is already deployed in some cars and coming soon in a few others, there are still many details that will need to be worked out as the technology moves into the mainstream.

For instance, the DOT has mandated that V2X systems not broadcast information that can identify individual vehicles. Also, advocates—including Consumers Union, the policy and mobilization arm of Consumer Reports—have stressed that security and privacy must remain a priority if vehicles are to be constantly communicating critical information to the world around them.

The communications standards for V2X, known as Dedicated Short Range Communications, could also allow for information and entertainment to be broadcast to vehicles. No one has yet nailed down exactly how this would work or even what services could be sent to cars. But if the screens in cars are subject to bombardment with ads and entertainment, that could cause driver-distraction concerns.