Submarines and radio don’t mix. Ever since World War I, engineers have struggled to find a way for the vessels to communicate when they’re fully submerged. After all, a submarine is at its most vulnerable when it surfaces, which submarines must still do today in order to broadcast a message.

Now, a team at MIT has developed a technique for an underwater source to communicate directly with a recipient above the surface. And it could be useful for more than just submarines—underwater exploration and marine conservation could benefit as well.

The challenge that has stymied submarine communication for more than a century is that what works well in water doesn’t work so well in the air, and vice versa. “A wireless signal works well in a single medium,” says Fadel Adib, the principal investigator for MIT’s Media Lab, where the technique was developed. “Acoustic works underwater, radio frequencies in the air.”