What Is a CMP?

A Consent Management Platform (CMP) is a tool, like OneTrust or Cookiebot, that displays a cookie or tracking consent banner, records a visitor's choices, and communicates those choices to other technologies on the site. A CMP records consent; it does not, on its own, prevent tags from firing regardless of what a visitor chooses.

This is the most misunderstood point in consent compliance, and it’s why Pre-Consent Firing and Post-Opt-Out Firing both happen on sites that already have a CMP installed: a CMP is a signaling layer, not an enforcement layer. Whether a tag actually respects that signal depends on how the Tag Management System (TMS) is configured; the CMP has no ability to reach into a tag and stop it. Consent Simulation is the only way to verify enforcement is actually happening, rather than assuming it because a CMP is present.