The "last mile" conundrum of how to deliver broadband connectivity from a communications provider to a customer's home is famously known in telecommunications circles. Less often acknowledged but equally vexing is the last-mile challenge faced by marketers in moving prospects from initial click-through to regular customers. In the conversation below Chad Little, founder of retargeting specialist Fetchback, outlines a new orientation to marketing's last mile, one he calls "post-visit marketing."

Behavioral Insider: Retargeting has of late become a very fashionable term. Many, if not most, large ad networks, for instance, offer what they call retargeting. How is what Fetchback's doing going to be different?

Chad Little: The analogy I like to make is going to a heart surgeon versus going to the family doctor. Both have their role, but one is infinitely more expert in a particular area. So as far as retargeting goes, yes, many ad networks include retargeting capability within their network -- but what we aim to be is the heart surgeon, the specialist within this realm.

The main difference is that we show how retargeting can be correlated to reach. If an advertiser works with an ad network, even if they do it well, their reach is limited to specific publishers on the network. But the potential universe for retargeting is far broader than that. What's been missing is a single interface to work across all the publishers and networks you deal with -- a single interface for developing and customizing creatives, tracking and monetizing potential customers who've already visited your site.

BI: How specifically does it work?

Little: Advertisers add a single line piece of code to specific Web pages they want to retarget. Each visitor to the site receives an anonymous cookie, which is then tracked by FetchBack wherever they go. Based on the guidance provided by an advertiser or agency and our own proprietary technology, ads can then be customized by ad types, units, sizes, frequency and content.

BI: What are the biggest gaps you see in how retargeting is currently understood?

Little: All of the financial and intellectual resources on the buy-side have been devoted to the front end, to creating the lead. But as marketers become more ambitious and learn to demand more efficiency in their spending, it becomes obvious that it's a lot more expensive to get that first cold lead than to resell to people you know are already interested. Many marketers only look at retargeting as a way of repurposing the same ad that brought the consumers to their site in the first place over and over again. What's been missing in retargeting is the ability to target a more specific and customized message.

BI: What are the biggest challenges advertisers face when trying to implement a retargeting strategy?

Little: Lots of advertisers don't know what to say, literally. They've never really thought through how to creatively keep the dialogue going once an original ad has made whatever impact it's going to make.

BI: What is the ROI case for retargeting as you explain it?

Little:Post-visit targeting, as we call it, isn't meant to be an investment used in place of front-end spending. In that sense it means advertisers do need to spend incrementally more overall. But the value proposition is compelling. The additional spending is best thought of as a way of recouping a portion of money from visitors who would otherwise be lost.

 Payment is on what we call an 'investment per visitor' basis. So if you've spent, say, 50 cents a click-through to reach 10 thousand visitors. You've spent five thousand dollars and converted a miniscule portion, say 2% or 3%, which is actually quite good. You can stop there with 200 or 300 customers, or you can invest another few cents per visitor in trying to build a further dialogue with the other 9,700 prospects you've already attracted.

BI: How do you see the demand for post-visit marketing evolving?

Little: The initial goal over the next year or so is to make post-visit marketing a critical part of the planning cycle. Between here and there there's an education curve to traverse. Right now at least a third of the advertisers are simply not aware. They haven't yet considered how to recoup the 'loss' from their front-end ad spend. Another third are somewhat aware there could be another way to increase the productivity of their ad dollars, but just aren't sure how to get started. Then finally there's a third who are aware of the current gaps in how they deploy ad dollars and have been looking for a solution.