Every brief we take starts with the same two questions: what's the moment, and what's the number? The second question routinely produces silence. So here is the answer we wish more marketers walked in with — the four-number stack that covers nearly every activation, launch, showroom, or trade environment we build.
1. Footfall — did they come?
Total unique visitors through the experience, against a target set from venue traffic, media plan, and past comparables. Footfall is the top of the funnel and the easiest number to capture: entry sensors, beam counters, or staffed clickers on smaller builds. The discipline isn't the counting — it's setting the target before doors open. A number without a target is trivia.
2. Dwell — did they stay?
Average time a visitor spends inside the experience. This is the number paid media can't touch: a feed impression is measured in fractions of a second, while a well-designed spatial experience holds full attention for minutes. Dwell is engineered, not hoped for — it's a direct output of spatial sequencing and emotional pacing, where the peaks land and where the room lets people breathe. If dwell is flat, the experience design failed, not the audience.
3. Capture — did they take it with them?
The share of visitors who photograph, record, or share the experience — plus the contact data the build collects: scans, sign-ups, RSVPs. Capture is where the physical moment becomes digital reach and pipeline. It's also the most designable number of the four: a deliberate photo moment, lit and composed to travel, will outperform an accidental one by an order of magnitude. Design for the walk-in moment and the moment they post about it.
4. Signal — did it move the business?
The metric behind the metric: earned media value, branded search lift during the activation window, qualified leads, appointments booked, sales in the surrounding period. Signal is the hardest of the four and the one your CFO actually reads. It requires agreeing attribution rules up front — which window, which codes, which baseline — so nobody argues about the math after the fact.
The part most teams miss
The stack only works if measurement is part of the build, not an afterthought. Sensors need power, sightlines, and mounting designed into the fabrication. Interaction logging needs the interactive tech built by people who talk to the people cutting the panels. This is the practical argument for keeping an experience under one roof: when the same team designs, builds, and instruments, evidence is native. When it's split across four vendors, measurement is everyone's suggestion and nobody's job.
Evidence it worked — the number. It's the final letter of our SENSE check, and nothing ships without it.
Before your next activation, write the four numbers down with a target next to each. If any target draws a blank, that's not a measurement problem — it's a brief problem, and it's fixable this week, not after the build.