# Session Enrichment

> The process of attaching customer, transaction, and context data to a visitor's session so the conversions that follow carry richer, higher-matching signals.

Session enrichment is the process of attaching customer, transaction, and context data to a visitor's session so that the [conversions](/glossary/conversion) which follow carry richer, higher-matching signals. AnyTrack joins client-side and server-side data on the [Client ID](/glossary/client-id) into a single enriched profile, then uses it for identity resolution and for raising [Event Match Quality](/glossary/event-match-quality) when conversions are forwarded to ad platforms.

## Session Enrichment vs Customer Data

- [Customer Data](/glossary/customer-data) — the personal information (email, phone, address) that gets added; session enrichment is the *act* of adding it to the session and tying it to the original click.

## How AnyTrack performs session enrichment

The [Tracking Tag](/glossary/tracking-tag) opens a session and collects first-party data (UTM parameters, referrers, the `_fbp`/`_ga` cookies, IP, user agent). As the visitor submits forms or your backend fires webhooks, AnyTrack appends [traits](/glossary/traits) and transaction data to that same session, matched by [Click ID](/glossary/click-id) or external ID. Customer PII is stored securely for enrichment and identity resolution, and is hashed with SHA-256 before any of it leaves AnyTrack for an ad platform.