If you do not want a contact to appear in the Sentinel directory for any reason you can specify that in the settings tab of the contacts profile by following the below steps.
- Click on the 'System' tab and the 'System Contacts' link.
- Press the 'View' button for the contact you wish to edit.
- Select 'Settings' tab.
- Select 'No' for setting 'The contact is visible in the app directory'.
- Press the 'Save Changes' button.