Brand marketers are shifting their focus away from traditional digital metrics like the click and toward new metrics such as attention.

How did we get here? Virtually every year there has been some sort of innovation: new ad sizes, formats, functionality, targeting and re-targeting techniques and programmatic buying methodologies. We have seen quite a transformation from the day the first 468×60 banner ad was put on a website and the user was encouraged to click.

While the innovations in general have been tremendous, we have actually seen a surprising lack of innovation around ad measurement. Direct response advertisers use “the click” as a proxy for success, but brand advertisers have never really had a true success metric to call their own, and finding the right metric for brands has actually proven a fairly hard problem to solve.

How should we go about finding the right success metric for brands? As a starting point, branding by definition is about creating an ongoing connection with a consumer, so that if and when they are in the market for your category of products, they consistently put you at the top of their consideration list.

Does brand advertising work by showing an ad once and getting an instant response? Of course not. Branding is about storytelling. It’s about an idea and trust. The connection that brand advertising creates takes time.

We don’t feel trust with a brand the moment we see a single ad or hear about a brand. The relationship has to be built over time and with consistent and repetitive positive experiences.

That special connection, that trust, creates what Warren Buffett calls an “enduring moat” for the brand. For the best brands, that moat is almost unbreachable. That’s a long way of saying there’s no shortcut to brand building.

Most branded products are still bought offline

A major challenge for brand marketers is that most brand-influenced products still generate the majority of their sales offline. When was the last time you bought a Coca-Cola or a Pepsi beverage online? How about a box of cereal? Or a car? How about a million-dollar consulting contract for your business?

There are exceptions, of course, but when you look at the numbers, the staggering conclusion is that most purchase behavior is still happening offline. According to the U.S. Department of Commerce, of the $1.17 trillion spent in the U.S. in retail in the second quarter of 2014, only 6.4 percent was ecommerce.

On the other hand, as most of us know and experience, we now spend more time online than we do in any other individual medium, including TV. Our lives are becoming digital.

So how should a marketer effectively and efficiently leverage digital for brand building?

Viewability is a good start

The currency of digital advertising for the last 20 years has been premised on the idea that an “impression” means an ad was served in front of a person who had a chance to see and be impacted by that ad. It turns out though, that premise may not be exactly true.

More than half of all display, mobile and video advertising bought on the Internet today is not physically viewable. In other words, the person who was intended to see the ad not only didn’t see it, they never even had it on their screen. How can we expect to measure and drive success if the ads are not even there? We can’t.

Viewability is a critical first step to success, because, said simply, if your ad wasn’t there, not much else matters. This is part of the reason why buying viewable impressions has become such a hot topic lately. There is not a single brand marketer who wants to buy an impression that was impossible to see. The transition that we are currently undertaking in the industry, from transacting on a served impression to a viewable one, will be painful for some and beneficial for others. It is absolutely necessary though.

Attention, the new currency

Will viewability solve all of our problems? Does buying a viewable impression mean that the ad will be effective? Relative to buying a non-viewable impression it certainly is better, but ultimately it simply means the ad was there and the person had a chance to see it, not that they actually saw it or were impacted by it.

We need to know not just whether the ad showed up, but whether the person was paying attention. That attention is the most important and most scarce resource that exists. It is what we all have a very limited amount of and what marketers value most.

Also, the way we pay attention has changed in recent times. How often do you sit and spend focused time on one site, never flipping between tabs? For most of us, it’s pretty rare. Whenever we are doing one thing, we are also doing another. That means our attention is fragmented and often unfocused.

So how do we go about measuring and ultimately getting attention? First, we have to define it. Second, we have to ask new questions and seek to discover metrics that may help us uncover attention.

Attention metrics

Attention literally means “notice taken of someone or something.” In the metrics world, starting with “was the ad there” makes for a logical first step (viewability).

After I know the ad is there though, I might ask how long it was there (in-view time) and how long the person was on the page (active page dwell time). Maybe I want to know whether the person interacted with the ad (universal interaction). How long did that interaction last (universal interaction time)? Did they hover over the ad (hover)? Did they touch it on a mobile device (universal touch)? Did they do anything else that tells me they are paying attention (perhaps metrics like scroll rate, scroll depth and scroll velocity can be informative)?

All of these “attention metrics” serve the purpose of giving the marketer a better understanding of the environment in which the ad was displayed. Armed with that information the marketer can make smarter decisions. They can buy inventory with more attention. They can optimize campaigns toward attention signals. They can even transact on attention.

The big innovation for 2015 will be attention. Many of the world’s biggest marketers are already doing it and more will follow, and for those that don’t, they are losing out on the new attention economy for digital advertising.

This article originally appears on entrepeneur.com