With an explosion in the number of ad networks over the last 18 months, it has become increasingly difficult for agencies and clients to identify which network is their best long-term marketing partner -- the network that can deliver a brand's objectives year in, year out.

It will come as no surprise that I believe in the value that a strong network can provide a brand, but the operative word in that sentence is "strong." Ad networks are emphatically not interchangeable, and the business relationships you create in this sector can make a big difference in how well you exceed your business objectives.

As one of the pioneers in this space, I have seen a lot of brands and networks work together over the years. That experience has led me to conclude that there are nine key considerations that should be used to determine what ad networks a planner should choose to have as part of their marketing plans. In my experience, these factors are relevant to both the "vertical" ad network sector, as well as the "horizontal" or general market sector:

Take a look at your ad networks checklist.