diff --git a/inc/CalDAVPrincipal.php b/inc/CalDAVPrincipal.php
index d86fc460..512a7fb4 100644
--- a/inc/CalDAVPrincipal.php
+++ b/inc/CalDAVPrincipal.php
@@ -65,27 +65,27 @@ class CalDAVPrincipal
   /**
   * @var RFC3744: The groups in which the principal is directly a member.
   */
-  var $group_membership;
+  protected $group_membership;
 
   /**
    * @var caldav-cu-proxy-02: The principals which this one has read permissions on.
    */
-  var $read_proxy_for;
+  protected $read_proxy_for;
 
   /**
    * @var caldav-cu-proxy-02: The principals which this one has read-write prmissions for.
    */
-  var $write_proxy_for;
+  protected $write_proxy_for;
 
    /**
    * @var caldav-cu-proxy-02: The principals which have read permissions on this one.
    */
-  var $read_proxy_group;
+  protected $read_proxy_group;
 
   /**
    * @var caldav-cu-proxy-02: The principals which have write permissions on this one.
    */
-  var $write_proxy_group;
+  protected $write_proxy_group;
 
   /**
   * Constructor
@@ -196,6 +196,34 @@ class CalDAVPrincipal
       }
     }
 
+    $this->group_membership = null;
+    $this->read_proxy_group = null;
+    $this->write_proxy_group = null;
+    $this->write_proxy_for = null;
+    $this->read_proxy_for = null;
+
+    /**
+    * calendar-free-busy-set has been dropped from draft 5 of the scheduling extensions for CalDAV
+    * but we'll keep replying to it for a while longer since iCal appears to want it...
+    */
+    $qry = new PgQuery('SELECT dav_name FROM collection WHERE user_no = ? AND is_calendar', $this->user_no);
+    $this->calendar_free_busy_set = array();
+    if( $qry->Exec('CalDAVPrincipal',__LINE__,__FILE__) && $qry->rows > 0 ) {
+      while( $calendar = $qry->Fetch() ) {
+        $this->calendar_free_busy_set[] = ConstructURL($calendar->dav_name, true);
+      }
+    }
+
+    dbg_error_log( 'principal', ' User: %s (%d) URL: %s, Home: %s, By Email: %d', $this->username, $this->user_no, $this->url, $this->calendar_home_set, $this->by_email );
+  }
+
+
+  /**
+  * Split this out so we do it as infrequently as possible, given the cost.
+  */
+  function FetchProxyGroups() {
+    global $c;
+
     $this->group_membership = array();
     $qry = new PgQuery('SELECT * FROM relationship LEFT JOIN usr ON (to_user = user_no) LEFT JOIN role_member USING (user_no) LEFT JOIN roles USING (role_no) WHERE from_user = ? AND role_name = '."'Group'", $this->user_no );
     if ( $qry->Exec('CalDAVPrincipal') && $qry->rows > 0 ) {
@@ -241,20 +269,51 @@ class CalDAVPrincipal
         }
       }
     }
+  }
 
-    /**
-    * calendar-free-busy-set has been dropped from draft 5 of the scheduling extensions for CalDAV
-    * but we'll keep replying to it for a while longer since iCal appears to want it...
-    */
-    $qry = new PgQuery('SELECT dav_name FROM collection WHERE user_no = ? AND is_calendar', $this->user_no);
-    $this->calendar_free_busy_set = array();
-    if( $qry->Exec('CalDAVPrincipal',__LINE__,__FILE__) && $qry->rows > 0 ) {
-      while( $calendar = $qry->Fetch() ) {
-        $this->calendar_free_busy_set[] = ConstructURL($calendar->dav_name, true);
-      }
-    }
 
-    dbg_error_log( 'principal', ' User: %s (%d) URL: %s, Home: %s, By Email: %d', $this->username, $this->user_no, $this->url, $this->calendar_home_set, $this->by_email );
+  /**
+  * Accessor for the read proxy group
+  */
+  function ReadProxyGroup() {
+    if ( !isset($this->read_proxy_group) ) $this->FetchProxyGroups();
+    return $this->read_proxy_group;
+  }
+
+
+  /**
+  * Accessor for the write proxy group
+  */
+  function WriteProxyGroup() {
+    if ( !isset($this->write_proxy_group) ) $this->FetchProxyGroups();
+    return $this->write_proxy_group;
+  }
+
+
+  /**
+  * Accessor for the read proxy for
+  */
+  function ReadProxyFor() {
+    if ( !isset($this->read_proxy_for) ) $this->FetchProxyGroups();
+    return $this->read_proxy_for;
+  }
+
+
+  /**
+  * Accessor for the write proxy for
+  */
+  function WriteProxyFor() {
+    if ( !isset($this->write_proxy_for) ) $this->FetchProxyGroups();
+    return $this->write_proxy_for;
+  }
+
+
+  /**
+  * Accessor for the group membership
+  */
+  function GroupMembership() {
+    if ( !isset($this->group_membership) ) $this->FetchProxyGroups();
+    return $this->group_membership;
   }
 
 
@@ -403,7 +462,7 @@ class CalDAVPrincipal
           break;
 
         case 'DAV::group-membership':
-          $prop->NewElement('group-membership', $reply->href($this->group_membership) );
+          $prop->NewElement('group-membership', $reply->href($this->GroupMembership()) );
           break;
 
         case 'urn:ietf:params:xml:ns:caldav:schedule-inbox-URL':
diff --git a/inc/caldav-PROPFIND.php b/inc/caldav-PROPFIND.php
index 8c24ae94..35617828 100644
--- a/inc/caldav-PROPFIND.php
+++ b/inc/caldav-PROPFIND.php
@@ -260,9 +260,9 @@ function add_general_properties( &$prop, &$denied, $record ) {
   // TODO: this duplicates code below. if possible, do said code only once.
   if ( preg_match('#/[^/]+/calendar-proxy-(read|write)/?#', $record->dav_displayname, $matches) && isset($prop_list['DAV::group-member-set']) ) {
   	if ($matches[1] == 'read') {
-        $reply->DAVElement($prop, 'group-member-set', href_set_from_paths( $request->principal->read_proxy_group ) );
+        $reply->DAVElement($prop, 'group-member-set', href_set_from_paths( $request->principal->ReadProxyGroup() ) );
   	} else /* if ($matches[1] == 'write') */ {
-  		$reply->DAVElement($prop, 'group-member-set', href_set_from_paths( $request->principal->write_proxy_group ) );
+  		$reply->DAVElement($prop, 'group-member-set', href_set_from_paths( $request->principal->WriteProxyGroup() ) );
   	}
   }
 
@@ -365,16 +365,17 @@ function build_propstat_response( $prop, $denied, $url ) {
 function add_proxy_response( &$responses, $which, $parent_path ) {
 	global $request, $c, $session;
 
-  $collection = (object) '';
-  if ( $which == 'read' ) {
-    $proxy_group = $request->principal->read_proxy_group;
-  } else if ( $which == 'write' ) {
-    $proxy_group = $request->principal->write_proxy_group;
-  }
   if ($parent_path != '/'.$request->principal->username.'/') {
     return; // Nothing to proxy for
   }
 
+  $collection = (object) '';
+  if ( $which == 'read' ) {
+    $proxy_group = $request->principal->ReadProxyGroup();
+  } else if ( $which == 'write' ) {
+    $proxy_group = $request->principal->WriteProxyGroup();
+  }
+
   $collection->dav_name = $parent_path.'calendar-proxy-'.$which.'/';
   $collection->is_calendar  = 'f';
   $collection->is_principal = 't';
@@ -474,24 +475,24 @@ function collection_to_xml( $collection ) {
     // Caldav proxy (not described in rfc, but CalendarServer has it)
     if ( isset($prop_list['http://calendarserver.org/ns/:calendar-proxy-'.$collection->proxy_type.'-for'] ) ) {
       if ( $collection->proxy_type == 'read' ) {
-        $proxy_group = $request->principal->read_proxy_for;
+        $proxy_group = $request->principal->ReadProxyFor();
       } else if ( $collection->proxy_type == 'write' ) {
-        $proxy_group = $request->principal->write_proxy_for;
+        $proxy_group = $request->principal->WriteProxyFor();
       }
       $reply->CalendarserverElement($prop, 'calendar-proxy-'.$collection->proxy_type.'-for', $reply->href( $proxy_group ) );
     }
 
     if ( isset($prop_list['DAV::group-member-set']) ) {
       if ( $collection->proxy_type == 'read' ) {
-        $proxy_group = $request->principal->read_proxy_group;
+        $proxy_group = $request->principal->ReadProxyGroup();
       } else if ( $collection->proxy_type == 'write' ) {
-        $proxy_group = $request->principal->write_proxy_group;
+        $proxy_group = $request->principal->WriteProxyGroup();
       }
       $reply->DAVElement($prop, 'group-member-set', $reply->href( $proxy_group ) );
     }
 
     if (isset($prop_list['DAV::group-membership'])) {
-      $reply->DAVElement($prop, 'group-membership', $reply->href( $request->principal->group_membership ));
+      $reply->DAVElement($prop, 'group-membership', $reply->href( $request->principal->GroupMembership() ));
     }
 
   }