1. Branding or Performance. What's the main goal of your advertising efforts? Developing brand awareness or generating customers... Focusing on one of these goals will help you decide which ad networks to consider. Especially since ad networks are usually display (branding) or performance (generate customers) based. And how they price will tell you which is which. CPM pricing means branding, while pay per click, cost per action (CPA), and cost per lead (CPL) mean performance.

2. Broad or vertical approach. If your product has "broad" appeal then an ad network that reaches tens of millions of consumers makes sense. Otherwise, you may want to consider a "vertical" network that deeply targets your specific audience or industry of choice. Here's an easy way to think about it: major TV networks vs. cable TV... which would you want to advertise on?

3. Go global... or stay local. Location still matters! Reach prospects wherever they are but don't waste dollars on users that can?t become customers because of where they live. Many ad networks provide geographic targeting that can narrow the world down to the country, region, or city that you care most about. Not to mention, all the ad networks (and directories) that specialize in local advertising.

4. Size of budget. Many ad networks serve large brand marketers that spend $50,000+ per month to push their message. Sound like you... If not, then shy away from those which emphasize Fortune 500 advertisers on their website or in their sales pitch. And if your budget is a lot less than $10,000, you may need to focus on performance, vertical or local ad networks. But don't worry, these can work well too!