How to Keep Taxonomy and Catalog in Sync as Both Change

A taxonomy gets built once, usually during a big project — a PIM implementation, an ETIM adoption, a website relaunch. Categories get defined, products get assigned, everyone moves on. Then the catalog keeps growing. New suppliers bring product types the original taxonomy didn’t anticipate. Existing categories get stretched to fit things that don’t quite belong, because creating a new category feels like more process than shoehorning a product into an existing one.

Eighteen months later, the taxonomy that was carefully designed no longer reflects what’s actually being sold, and nobody planned a moment to notice — it just drifted, one slightly-wrong assignment at a time.

Why this is a continuous problem, not a one-time project

The taxonomy and the catalog aren’t static relative to each other. New product types arrive faster than anyone revisits category structure. Suppliers get onboarded with products that fit awkwardly into existing categories. Standards themselves update — ETIM releases new versions with new and retired classes periodically. Treating taxonomy as a project with an end date guarantees it’s out of date within a year.

This is a close cousin of classification drift — the difference is drift describes individual products landing in the wrong category over time; taxonomy sync is about the category structure itself needing to evolve alongside what the catalog actually contains.

What keeping them in sync actually looks like

Monitor for products that don’t fit well anywhere. A product force-fit into the least-wrong existing category, rather than a category that actually describes it, is a signal the taxonomy needs a new branch — not that the product was mis-classified by a person.

Re-evaluate category structure against catalog composition periodically, not just at initial build. If a category has grown to contain products spanning very different specs, it likely needs to split. If a category is nearly empty, it may need to merge or be retired.

Version the taxonomy and re-run classification against the new version, rather than manually re-tagging products by hand every time the structure changes. Products should be reassigned automatically when the taxonomy evolves, with confidence scoring flagging ambiguous cases for review.

Track standard updates (ETIM, eCl@ss releases) as an input to when your own taxonomy needs revisiting, not as a separate compliance exercise disconnected from your actual catalog structure.

Taxonomy feels increasingly out of step with what you actually sell? Book a 30-minute call.

Related reading

• Detecting and fixing classification drift
• Which classification standard should you use?

FAQ

Why does a product taxonomy go out of date? +

Catalogs keep growing and changing after the taxonomy is built, bringing new product types that don’t fit existing categories cleanly. Without a process to revisit the structure, products get force-fit into the nearest available category instead of a genuinely accurate one.

How often should a product taxonomy be reviewed? +

Continuously in principle — the practical approach is versioning the taxonomy and monitoring for products that don’t fit well, then re-evaluating and automatically reassigning rather than waiting for a scheduled, infrequent full review.