Momondo, a Copenhagen-based online fare aggregator and travel metasearch site that also owns Cheapflights.com, is now overseen by Steve Hafner, the CEO and co-founder of Kayak. (Priceline acquired Kayak in 2013 for $2.1 billion)

The online travel space has seen a ton of consolidation over the past few years, with Expedia now owning Hotels.com, Hotwire, Trivago, Travelocity, Orbitz, and HomeAway, and Priceline adding Booking.com, Agoda, rentalcars.com, and OpenTable to its brand portfolio.

The Momondo acquisition is part of Priceline’s goal to lure more travelers living outside of the U.S. According to Hafner, Momondo has “a similar mission to Kayak, but they’re leading in Europe.”

“All of these brands have similar visions, which is that we want to make online travel easier for people. We think the back-end technology at Kayak is superior to what they’ve built. The goal is to have the Kayak back-end to power their front end and have a better product and service.”

Hafner also says online travel technology is moving toward more chat bots and the use of artificial intelligence. Kayak recently rolled out a feature for Amazon Echo users, though he admits that the search technology is limited and doesn’t give consumers the full experience of searching Kayak on a laptop or smartphone.

“We’re one of the first companies out there that allows you to book a hotel room using voice over Alexa,” Hafner told Fortune. “It’s best used right now for repeat bookings or same-day bookings.”

But one thing Kayak still can’t do is let its users book flights on Southwest or stays at an Airbnb. Watch the video above to find out why.