Segments before individuals
One-to-one personalisation sounds better than it usually performs, because it needs data that is accurate, current and lawfully usable for each person, and content that makes sense in every combination. Segment-level personalisation, by market, language, product owned, life stage or lapsed versus active, captures much of the relevance with far fewer ways to go wrong. AI changes the economics: a distinct creative for each of forty segments is now practical, where it once meant forty shoots. Start with segments whose needs genuinely differ, and personalise individual fields, such as a name or nearest store, only where the data is reliable.
Data and consent boundaries
Personalisation runs on personal data, so the law sets the edges. Under GDPR you need a lawful basis for the profiling behind it, and people can object to profiling for direct marketing at any time, with no balancing test. Inferring sensitive traits such as health, religion or sexuality from behaviour can create special category data and should be off limits for marketing. The EU Digital Services Act adds that online platforms may not show ads based on profiling with special category data, nor profiling-based ads to users they are reasonably certain are minors. Use only the fields a template needs, and never pass personal data to a model that retains inputs.
Templates with variables, tested at the edges
Personalised content is a template plus data, and the failures live at the edges of the data. Test every variable at its extremes: the longest name, a missing field, a name with an apostrophe or accent, a right-to-left language, a product with no image, a store that has closed. Define a fallback for each field, so a missing first name produces a sensible greeting rather than an empty gap. For generated imagery and video, lock what must not vary, such as product, logo and legal lines, and let only the variables change. Review a sample drawn from every segment, not just the default version.
Measurement and the creepiness line
Prove the effect with a holdout: a random group that receives the generic version, so any lift can be credited to personalisation rather than to timing or the offer. Then watch the creepiness line. Using a customer's city or last purchase feels helpful; referencing something they browsed once, a life event they never shared or a price they almost paid feels like being watched. A useful test is whether the customer would understand how you knew. In the studio, batch generation can run from a product feed with the brand hub's approved claims and banned words enforced at generation, so versions stay on brand as they multiply.
Updated 25 September 2026 · General information, not legal advice. Rules change, so check the current text with your legal team before relying on it.