DAVOS • Evangelists for driverless cars see a bright future coming down the road: thousands of lives saved, countless driving hours freed up, cityscapes transformed with traffic jams vanquished.
But the new technology also threatens millions of jobs and raises a slew of ethical dilemmas - prospects that were on the minds of business chiefs and politicians meeting at the World Economic Forum this week.
"Companies are going to have to start thinking about it, governments are going to have to start thinking about it," said Professor Missy Cummings, director of the Humans and Autonomy Lab at Duke University in North Carolina.
"The reality is, we can't just keep our head in the sand like an ostrich," she said, singling out the coming impact on employment.
In the United States alone, an estimated four million people work as truckers, taxi drivers and in other jobs that will be under threat when driverless vehicles come into widespread use - a matter of years, experts predict.
In October, a self-driving truck built by Uber's Otto unit successfully delivered a beer shipment.
Cars with some autonomous functions - such as the ability to adjust the speed - are already on roads, and more than a dozen automakers, including BMW, Kia, Volkswagen and General Motors, are racing to get fully self-driving cars to market by 2020.
The technology's champions note its potential to reduce the 1.3 million road deaths worldwide each year - too many at the hands of a tired or distracted driver, or one who did not react fast enough.
The industry is already changing quickly due to the advent of services such as Uber and electric vehicles, and carmakers are eyeing both the threats and opportunities.
Renault-Nissan chief Carlos Ghosn summed up the transformations as a "reshuffling of the cards" for the industry. "There is a new game, let's see who is going to be able to prevail," he said in Davos.
The dash for driverless technology is bringing new players into the car business, notably Google, Apple and BlackBerry. The disruption will create jobs too - engineering posts and roles in new services. There is talk of mobile doctors' surgeries and moving nail salons.
But the transition will be painful, not least because most cabbies and truck drivers are not qualified to slide seamlessly into new roles.
The question of how to regulate the new vehicles is giving the authorities around the world a headache. Ms Inga Beale, chief executive of the Lloyd's of London insurance market, said insurers were grappling with the question of liability in case of an accident.
The US government unveiled a regulatory framework in September, but carmakers also have to deal with ethical and legal dilemmas.
At the extreme end, if an intelligent car is faced with the choice of killing one person to swerve around a crowd of five, what should it do?
There was some relief for the industry when the US government this week found no safety-related defect in a fatal crash involving a Tesla car on autopilot last May.