When you launch a digital campaign, one of your first priorities is to decide where to purchase your inventory - do you want to buy it directly from your publisher or go through an ad exchange? In this guest article Martin Brown, UK managing director for DataXu explains the key strategies for buying that all-important digital collateral. This article is copyright 2014 The Best Customer Guide.

When it comes to digital media, programmatic approaches can now be used on premium, directly bought media, as well as exchange traded inventory. The following are four of the key techniques for purchasing inventory, all of which should help you to deliver against your campaign goals:

  1. Direct Buys
    According to the latest IAB results, UK digital ad spend increased 15% year-on-year to £6.3 billion in 2013. Direct buys take the lion's share of this digital budget, and while we believe these are still an important part of the marketer's arsenal, they shouldn't be your main tool. They are useful if your goal is to raise widespread awareness for a product or brand and streamline your message for all readers. However, this approach does not always tailor the message to the unique profile and interests of the user who sees it.
  2. Direct Buys with Decisioning
    Direct buys that are complimented by a decisioning model are ideally suited for both brand and performance-based campaigns where customised messaging will deliver the best results. There are two techniques that drive decisioning - programmatic premium and dynamic creative - which can be used separately or in tandem.

    For example, by using the programmatic premium approach which uses first, second and third party data with predictive algorithms to infer consumer preferences, an auto manufacturer that wanted to target mums with mini-van ads and urban residents with compact model ads could purchase demographic datasets from Nielsen or BlueKai, and overlay it with eXelate 'auto-intender' data. This would help to differentiate between women with children and young urban professionals.

    With the dynamic creative route where ads are customised based on variables captured by the buying platform, such as consumer location, you can apply what you know about your customers to variables captured on the publisher's sites, such as IP addresses. So, visitors will get ads for their local dealership, based on their IP address.

  3. Private Exchanges
    Private Exchanges are a great middle ground between premium direct buys and programmatic, auction based buying. In private exchange scenarios, publishers wall off parts of their inventory and make them available to selected buyers. Buyers pay for this special access to better inventory through higher CPMs, but just like open ad exchanges, you're not obligated to purchase an available impression if a user doesn't meet your campaign criteria.

    Private exchanges are ideal when a reasonable portion of a publisher's readership overlaps with your target audience, and the site attracts an adequate number of users to target. But purchasing inventory via a private exchange can get pricey if it doesn't offer scale you need. In such cases, an open exchange is the best option.

  4. Open Exchanges
    If your target audience is relatively small, or can't easily be found on a national site, the real-time ecosystem is your best bet. Like private exchanges, they can be selective about which impressions you buy, leveraging first, second and third party data to build nuanced profiles of the user behind each impression.

    Aggregating inventory from hundreds of publishers of all sizes which means they offer massive scale - billions of impressions reaching 100 million unique users per month. Most ad exchanges have also now implemented exhaustive screening processes that review all inventory to ensure brand safety and to prevent ad clutter.

    Most importantly, publishers are beginning to embrace programmatic selling, and are starting to offer premium inventory to the ad exchanges. Some, such as Federated Media, have abandoned their direct sales channel in favour of selling 100% of their inventory programmatically.

"So, going back to our opening question - where should you get your inventory for your digital campaigns?" asks Brown. "Obviously, the answer has to come from your campaign goals."