The gap between BT technology and an ad network is almost non-existent now, and you can get the efficiencies of BT on more than just the single site level-- let's look at how BT changes when you go from measuring behavior on a single site to tracking behavior across multiple sites.

On-site scenario: A travel client we'll call TravelBizUSA wants to reach frequent business travelers. Its ads are running on travel sites, but they are reaching business and leisure customers; it's difficult to isolate these two audiences. So they go to sites that would reach this audience (think Wall Street Journal, Forbes, et cetera) and run a BT campaign with them. 

Takeaway: As much as this travel client would like to use BT on each site they think has their audience, the travel sections of these sites are small and don't allow the travel advertisers to achieve much scale in reaching a travel BT audience just on that single site. While this is improved targeting compared to just running ROS, it is limited by reach. 

BT is a great addition to the technology that sites have to reach users, and advertisers are thrilled to find new ways to reach users when content they so desired had sold out.

But there are better ways to use BT on a greater scale, such as cross-site targeting.

Cross-site scenario: Let's revisit this same travel advertiser, TravelBizUSA. It wants to get more scale and reach out of its BT program, but inventory keeps getting tighter and more expensive. TravelBizUSA needs a way to find greater scale at an ROI that makes sense for them. TravelBizUSA approaches the BT ad networks to find out what they offer. It turns out TravelBizUSA can reach these premium frequent business travelers (FBTs) on these networks with a reach much greater than if they worked with each individual site. TravelBizUSA works with the BT networks to come up with the most accurate FBT profile, based on the segmentation these networks have, and build a campaign to reach FBTs. This includes a pixel on the TravelBizUSA home page, as well as their confirmation page. 

These BT networks will buy the inventory -- mostly remnant -- from the publishers ahead of time and make sure that inventory fits the travel client's needs. Whatever doesn't fit can be passed back and exchanged for inventory that does work. The nice thing is that most BT networks are transparent to keep this high-profile brand off of offensive/controversial sites, though sites cannot be cherry picked since this goes against the grain of what these networks can provide. It's not about the site, it's about the behavior. 

Takeway: The advertiser now has greater scale of their BT program with these broader channels (BT networks). And in addition to targeting that the BT network can already provide, advertisers can now also build a greater network of people to reach on all these sites based on the profiles of users already coming to the travel client's site. The more learning the networks' technology does, the greater the accuracy of the targeting.

And the publishers TravelBizUSA are working with through the BT network are happy because they can now generate greater revenue for what was considered remnant. It is far more valuable based on users' behaviors, and TravelBizUSA will pay more for that increased targeting.

Those are the basics. Now let's move on to the next level.