The digital ad industry has placed a lot of effort behind innovating within the process of planning and buying. Here's what needs to be delivered with the next wave of planning and buying tools.

Process makes our brains hurt. It's actually painful to take the digital media buying and planning process, break it down into its component tasks, and describe those tasks to people who design applications. That last translation piece is particularly heinous -- breaking process down to things that exist in database tables for which there are rules and exceptions.

Yet that's precisely what media planners have had to do. They've had to do it on a fairly continual basis for at least a dozen years, so that ad management companies, search management companies, ad exchanges and even ad sellers could develop tools to make it easier for their best customers to purchase media from them and keep track of it all.  Moreover, the constant change in our business has made maintenance of these tools a constant, iterative process of feature development and deployment.

The first agency-side ad management companies did an admirable job of taking care of the first big task that fell to digital agencies -- serving ad creative for campaigns and keeping track of impressions and clicks. Before that problem was solved, running big campaigns was a 24-hour-a-day job characterized by constant trafficking instructions zipping back and forth between agencies and publishers via email, and by crunching log files to get a gauge on performance. That's what the First Wave of agency tools was all about: ad serving and reporting.

The Second Wave was all about streamlining the process of getting a large number of Requests for Proposal (RFPs) out the door, managing/evaluating the responses from publishers and distilling that into a client-ready recommendation. Prior to the innovation in the Second Wave, this process was also a mess, best described as a flurry of email and Excel attachments that drove everybody involved completely bonkers.

The Third Wave was all about buying interfaces that made it easy for media buyers to book inventory with certain ad sellers on certain mutually agreeable terms. I lump ad exchanges and things like Google's ad engine together in this category. What exists here certainly does save media planners and buyers time and effort, but in many cases these systems are actually generating more work due to their complexity and limited utility.

I think that the coming Fourth Wave, which most would argue is already underway, will solve more problems than it creates. This Fourth Wave, in order to be successful, should focus on the management of an increasingly dynamic digital ad marketplace. There are so many ways to apply the descriptor "dynamic," so let me be specific about what I mean here.

The ad marketplace is becoming increasingly dynamic. Inventory is fluid. The same impression is available to a theoretically unlimited pool of advertisers at a wide range of price points, through a wide variety of targeting filters. Perhaps most importantly, though, that impression is available to the pool of advertisers via a number of sellers.

Ad management solutions from the prior three waves have been static in that they depend on a particular impression (or series of them) being married to a particular ad seller. If the next wave of tools is able to adjust to the fluid dynamics of the marketplace, planners and buyers will be able to look at the ad market as a whole.

To an extent, ad exchanges have latched on to this concept, but their utility and continued existence is predicated on the notion of static seller participation. By its nature, this limits the ability of the planner using the exchange to look at the market as a whole.

Whole-market visibility is critical to the planner's ability to size up opportunities for clients in the digital sphere. Agencies need to be able to deliver prototypical plans to their clients with budgets and levels attached, so that clients can assess the relative value of the digital channel vis-à-vis television, radio, magazines and other offline media.

So, I think the ad management company that dominates the Fourth Wave of planning and buying tools will be the one who figures out how to make the dynamic ad model work.

Tom Hespos is the president of Underscore Marketing and blogs at Hespos.com.