3. If you're comfortable disclosing this information, which network do you use? Why did you choose it?

Sean X Cummings, director of marketing for Ask.com:
We've used every major network and constantly test new networks every quarter for performance. Not all ad networks are equal, and not all are equal for each business. A network that performs great for one client may tank for another; that is what surprises most brands. They hear a brand espousing the virtues of a certain network, try it out and their program tanks… and then think either they are doing something wrong, or the other brand does not know what they're doing. There is the illusion that because many networks can provide mass reach, that it means mass consumer. The type of ad placements within a group of sites will be quite diverse. Sure, you may be buying skyscrapers and leaderboards, but where they are on the page has as much influence as what site it is on. Those various combinations of the assemblage of sites within an ad network create a psychographic persona of sorts for that network. It is not about demographics, but psychographics, and the mindset of those consumers when they are on those grouped sites.

Bill Daley, senior manager, interactive marketing for Universal Orlando Resort:
The ones we use the most are Undertone, Specific Media, Advertising.com and Vendare. We also use the MSN Direct, which is like a network buy within the MSN sites. They work the best for us in regards to site conversions, and duplication of websites within these networks is minimal.

Valerie Constable, director of media at Kaiser Permanente:
We've used many including Tribal Fusion, Specific Media and Advertising.com. We apply some internal controls and calculate marketing costs per (potential) member. We've used more general networks, rather than health-oriented ones. Sometimes health content is applicable if we agree with it. We do contextually target, for example, expectant mothers, but we're just as likely to behaviorally target. We re-target too. We have a re-contact strategy that we've only been using for a few months, but we've already seen a significant lift.

Keith Pieper, director of performance media at Universal McCann, on online campaigns for client Microsoft:
Aside from niche networks and nuance features, ad networks in general offer a commodity product -- i.e. massive reach at a relatively low cost -- and they can scale fast. Aside from price, what really makes one network different from another is an understanding of our needs and business, which comes down to service. In our experience, service is a differentiator between ad networks.

Kyle Sherwin, media director at Sony BMG:
We've used Specific Media, Collective Media, Undertone Networks and ValueClick. Other companies like Gorilla Nation that are not technically networks also serve similar functions for us. We have used Advertising.com but since they're not transparent, we've shied away more recently. For a more broad-based artist, we'll use networks with the most popular sites (i.e., Comscore 100 or 200). Sometimes we'll work with networks with thousands of sites because they have properties that attract the right influencers and specialized music genres.

Katelyn Himes, manager of online marketing for La Quinta Inns & Suites:
Without giving away too many secrets, we work with some of the top networks out there and continuously test new opportunities.

Katie McCormick, web manager at Revlon:
We use ValueClick and Advertising.com because they are the best known and came to us with the best proposals.