Amazon’s purchase of Whole Foods is intriguing news that’s been covered by just about every major media outlet, but the company quietly announced another addition to its capabilities in the past few weeks. One that marketers may find even more exciting.

Amazon, in its blog post , describes Advertiser Audiences as “a new self-service capability that allows advertisers to securely engage their customers and extend campaign reach on and off Amazon.” If you haven’t yet considered Amazon as an advertising channel, this could be a good time to start testing.

Advertiser Audiences allows you to reach existing customers – of which Amazon says case study participant Burt’s Bees saw click-through rate increase by 2x, consideration rate increase by 9x, and purchase rate increase by 4x to 8x – but the real power lies in creating lookalike audiences. To do that, advertisers anonymously match a list of their customers with Amazon shoppers to create new targeting segments to use in Amazon advertising campaigns.

Pros of Advertiser Audiences

Unlike other platforms like Facebook, Twitter, and even Pinterest, people looking at Amazon are the farthest along the funnel, and couldn’t be closer to a purchasing decision. This allows marketers to shape messaging accordingly. Instead of spending time and money on ads that inform, educate, or interest, messaging can be much more blunt and aggressive.

While you won’t get direct insight into Amazon’s customers, campaign results, if interpreted correctly, will reveal behavioral data for those people who have made it nearly all the way through the funnel. This information can inform future advertising decisions, even outside of Amazon campaigns.

Cons of Advertiser Audiences

Currently, Advertiser audiences is not an easy-to-use, intuitive platform. It’s a manual process that unless you’re experienced (or very patient) may require agency assistance.

As mentioned above, the tool will help you reach lookalike audiences, but don’t expect a huge dump of data in return. Some analysts have described Amazon’s advertising offerings as “black-box,” and this one is no exception.

Only Amazon advertisers (advertisers placing buys directly with/through it) have access to the channel and can use it only for their Amazon campaigns.

Advertiser Audiences In Action

Amazon worked with Burt’s Bees to test and ramp up Advertiser Audiences. Over the last holiday season, Burt’s Bees wanted to focus on their gift packs and stocking stuffers. Using Advertiser Audiences, they discovered 68% of their website customers also used Amazon for online purchases. They used that info to build a lookalike segment and saw that matched customers purchased 4x more.

How to Get Started

Though technically Advertiser Audiences is a self-serve platform, Amazon suggests you contact your account exec to get started. Pay close attention as he or she walks you through the process so you can take over from there and not have to depend on someone else to launch future campaigns.

As part of Amazon’s terms to use Advertiser Audiences, you will need to anonymize your customer email list using either a self-service user interface or if you know how, you can pre-hash your list before submission. (A search for “SHA256 generator” turns up quite a few encryption options. SHA256 refers to the algorithm that carries out the anonymizing).