Contactless payment systems have made a big splash in Europe, and they’re catching on in other places as well.

However, in the United States, the contactless approach hasn’t gained the traction that some might have expected.

A new study from the New York Times, however, says that may be about to change, as mobile wallets—particularly Samsung Pay and Apple Pay—are increasingly popular and will likely be only more so in the weeks ahead.

The Times, with some research from ABI Research, noted that contactless card shipments are expected to reach 330 million units by the dawn of 2020, or accounting for better than one in every two cards, at 55 percent of the total.

That’s a good number, but it’s only better when compared against 2015 levels, which were right around 25 million. In fact, Europe is expected to reach 420 million units by 2020, about 75 percent of all newly-issued cards, a hefty 75 percent of the total.

Essentially, as ABI Research’s Phil Sealy notes, the difference between the two is a textbook separation between an emerging and a maturing market.

Thus, education will be particularly important to get the largest penetration into the market and make these projected numbers into reality.

However, there’s a point both Sealy and others like Newcastle University’s Martin Emms make: contactless payment systems have some significant security issues that still remain to work out.

This is where the “education” portion will take hold the best; contactless is still comparatively new, and many places won’t actually accept it.

While some places are taking Europay / Mastercard / Visa (EMV) transaction systems, and others are taking mobile payments, it’s only a fairly small cross-section that’s actually taking both at the same time.

The more places that accept contactless, meanwhile, the faster the growth rate will be overall. It’s going to require that user base in order to really have any traction, and unless contactless can make a case for itself, the Times’ and ABI Research’s numbers likely won’t hit.

So in the end, a combination of education—for both users and retailers—and expanded use bases will likely send contactless soaring in the US. Without these points, contactless will simply not make contact in the levels hoped for.