public function Delete($UserID, $Options = array()) {
      if ($UserID == $this->GetSystemUserID()) {
         $this->Validation->AddValidationResult('', 'You cannot delete the system user.');
         return FALSE;
      }
      
      $Content = array();
      
      // Remove shared authentications.
      $this->GetDelete('UserAuthentication', array('UserID' => $UserID), $Content);

      // Remove role associations.
      $this->GetDelete('UserRole', array('UserID' => $UserID), $Content);
      
      $this->DeleteContent($UserID, $Options, $Content);
      
      // Remove the user's information
      $this->SQL->Update('User')
         ->Set(array(
            'Name' => T('[Deleted User]'),
            'Photo' => null,
            'Password' => RandomString('10'),
            'About' => '',
            'Email' => 'user_'.$UserID.'@deleted.email',
            'ShowEmail' => '0',
            'Gender' => 'u',
            'CountVisits' => 0,
            'CountInvitations' => 0,
            'CountNotifications' => 0,
            'InviteUserID' => null,
            'DiscoveryText' => '',
            'Preferences' => null,
            'Permissions' => null,
            'Attributes' => Gdn_Format::Serialize(array('State' => 'Deleted')),
            'DateSetInvitations' => null,
            'DateOfBirth' => null,
            'DateUpdated' => Gdn_Format::ToDateTime(),
            'HourOffset' => '0',
            'Score' => null,
            'Admin' => 0,
            'Deleted' => 1
            ))
         ->Where('UserID', $UserID)
         ->Put();

      // Remove user's cache rows
      $this->ClearCache($UserID);
      
      return TRUE;
   }