By Dan Bayford, OOH Partner, Posterscope
Programmatic DOOH is a hot topic right now, with lots of noise, competing agendas, and a fair bit of confusion. Here’s my attempt to cut through the clamour and the hype.
Programmatic is an exciting way to trade OOH. It unlocks the potential to build incredibly effective, precisely timed campaigns, and it should absolutely be in your agency’s wheelhouse. But it’s just one way to trade, it’s not the default and it shouldn’t be.
What makes Programmatic DOOH different from other programmatic media is that DOOH is a finite medium. That creates real trade-offs: what you gain in flexibility and waste reduction, you sacrifice in guarantee and specificity.
A useful analogy is to imagine you are booking a holiday. If you have a fixed two-week window and you’re set on a particular resort in the South of France, you book early, because you want certainty. The exact place, the exact time, the exact quality. Yes, you’re committing before anything uncontrollable shows up: a summer cold, a week of rain, an Icelandic ash cloud (2010 — simpler times!). But the certainty is worth it.
If your criteria are broader however (“any hot week in summer”) you can afford to wait. Book late, when conditions are known, and avoid paying for a week you can’t enjoy.. but you might find the best places already gone, or even that you can’t book at all. Supply is finite, and popular options get booked out.
OOH trading works in a similar way. Traditional buys are like booking the exact resort early (guaranteed display, specific locations, known timing). Programmatic is like waiting for the right conditions and moving fast; brilliant for optimising around moments, but not designed to guarantee specific inventory at exact times. Leave it too late, and you might find there’s nothing left to book.
Programmatic DOOH is brilliant, until the screen you want is already sold.
What about cost?
Comparing PrDOOH CPMs (which include tech and data fees) to broadcast OOH CPMs, in most cases, will leave you paying more for your programmatic impacts. But cost is a blunt instrument and doesn’t cater for effectiveness or wastage.
If you want to buy a specific Digital OOH site for a single hour where your audience over-indexes, traditional trading would command a significant premium. Programmatic CPMs may well be more efficient.
If your ad is only going to be relevant to people in a specific, unplanned moment, buying that traditionally means enormous wastage. Again, programmatic CPMs may well be more efficient.
Conversely, if you want a broadcast campaign optimised for all-adult CPMs, you’ll almost certainly get a better deal trading upfront in the traditional way.
It’s also worth considering the wider value of having your Digital OOH integrated into an omnichannel Programmatic approach. OOH is notoriously difficult to measure, but embedding it within a real-time ecosystem could surface powerful insights that offset any increase in CPTs.
So when should you use PrDOOH?
The honest answer is: it depends. Speak to your agencies, figure out your trade-offs, and consider the most effective way to approach the market. Briefs that simply ask for PrDOOH make me nervous; let’s start with what you want to achieve and your KPIs, and then choose the best method to make that happen.
But enough of sitting on the fence, here’s a practical guide:
Use traditional trading when:
- You must have specific locations (site specificity)
- The moment is known in advance (launch windows, fixed dates, tentpole weeks)
- You’re speaking to a relatively broad audience (cheaper broadcast CPMs)
- You need guaranteed display and predictable delivery (a week of patchy display would negatively affect your campaign)
Use PrDOOH when:
- The value lies in unpredictable moments (conditions you can’t confidently forecast weeks out)
- You’re activating trigger-based delivery (weather, traffic speed, footfall, etc.)
- You’re using targeting that would carry a significant premium (more efficient to trade using PrDOOH)
- You can tolerate non-guarantee due to availability constraints (a week without much display won’t derail your campaign)
- You can activate and optimise your PrDOOH as part of your omnichannel Programmatic approach (rich insights and integrated measurement)
And remember: you can use both. Mark Ritson is famously a big fan of ‘bothism’ and it applies here too. Build a traditional core that delivers the guaranteed coverage and frequency you need in the weeks you need it, then layer in a targeted PrDOOH strand to add relevant touchpoints. As my AI assistant poetically put it, using both a “guaranteed spine” plus “moment-based muscle”.
