Market-specific product data - sizes, compliance, and local conventions
Lesson two classified your data; this lesson works through the genuinely market-dependent class in detail, because it's where internationalization gets concrete and where fashion/lifestyle catalogs have the most exposure. The through-line: every market-specific requirement has a structural solution (conversion layers, conditional rendering, market-aware feeds) and a fork solution (duplicated data per market) - and the structural one always wins at scale.
Size systems: conversion, not duplication
The fashion classic: one garment is EU 38, UK 10, US 6, and "M" depending on who's asking. The structural pattern from lesson two, now in full: variants carry one canonical size (pick your system - usually your design/production system) in the option or a metafield; conversion tables (a metaobject or structured lookup) map canonical → per-market display; the theme renders the shopper's market's convention (with the others available - customers cross-shop conventions constantly, so "EU 38 / UK 10 / US 6" on the size guide beats hiding the mapping); and feeds project per market via the same lookup (Phase 7's tables - Google's apparel size values per country are themselves a spec worth matching exactly). What this prevents: the variant-title graveyard ("38/10/6-M") and the per-market duplicate products that size chaos otherwise breeds. One more Phase 2 dividend: this only works because size lives as structured data, not as text in a title.
Compliance content: the non-negotiable layer
Regulatory requirements vary by market and product category, and they're not optional: textile fiber-composition labeling (EU rules on fiber names and percentages - your material metafields, again, but rendered to spec), care labeling conventions, country-of-origin declarations, and the category-specific regimes - beauty/cosmetics ingredient disclosure (INCI - Phase 11 treats the full headache), electronics/toys safety marks, extended-producer-responsibility registrations (packaging and textile EPR schemes rolling out across EU markets, with per-country registration numbers that increasingly must be displayed). The implementation principle: compliance content is data plus per-market rendering rules, not per-market prose - fiber composition lives once as structured data and renders to each market's format; a compliance metafield set plus market-conditional theme sections covers most of it. And an operating principle: someone owns the requirements-per-market matrix and reviews it on a schedule, because these rules change and "we didn't know" doesn't work as a defense. For most brands this is an annual hour with your trade association's updates, not a legal department.
Units, conventions, and the courtesy layer
The smaller conventions that mark a store as genuinely local versus translated: measurement units (cm/inches on dimensions and size guides - render both where markets mix), currency formatting (Markets handles the currency; formatting conventions ride along), date formats in shipping promises, and local payment/delivery expectations messaging (less product data, more market trust furniture - but often stored and rendered through the same conditional mechanisms). Individually trivial; collectively they're the difference between "ships to Germany" and "German store." The audit that catches the gaps: one native speaker per market walks one full purchase path per quarter, noting everything that feels foreign. Twenty minutes per market, and it surfaces what no crawler can - the moments where your structurally elegant internationalization still reads as translated.