Keeping tabs on millions of shipping containers is difficult. But IBM and A.P. Moller-Maersk, the world’s largest container shipping firm, are building a blockchain they say will streamline the process and save billions of dollars.

The problem: International shipments pass through many hands, involving hundreds of communications. Keeping track of it all can account for 20 percent of the cost of moving a container, says Maersk. And a 2017 cyberattack revealed how vulnerable today’s system is to hacks.

The pitch: The two companies claim a blockchain-based platform will manage all that information more efficiently by providing a secure, trustworthy record of who has handled the shipments, and when.

But: Even if the technology works, the project will only succeed if all participants get on board. Maersk told Reuters that customs and port authorities in the U.S., Singapore, the Netherlands, and China’s Guangdong province are interested, as are “some other shipping companies.” There’s still a way to go.