 up</a><li role=none aria-label="See also"><a href=#see-also>See also</a></li></ol><hr></div></nav><p>This task shows you how to set up an Istio authorization policy using a new value for the <a href=/v1.15/docs/reference/config/security/authorization-policy/#AuthorizationPolicy-Action>action field</a>, <code>CUSTOM</code>,
to delegate the access control to an external authorization system. This can be used to integrate with <a href=https://www.openpolicyagent.org/docs/latest/envoy-introduction/>OPA authori