An access control list (ACL) is a list of access
  control entries (ACEs).  ACEs allow or deny access
  to commands and other CMS objects.

  For example, you can create an ACE specifying certain
  users who are not allowed to insert or modify a
  particular element.

  The use of ACLs could possibly cause unintended
  restrictions. You should fully understand the composition
  of both OpenVMS and CMS ACLs before using CMS ACLs. See the
  "Guide to DIGITAL Code Management System for OpenVMS
  Systems" for information on using ACLs.

  Choose the Set ACL... menu item to create, modify, or
  delete an ACL on various objects in the library.