diff --git a/sites/all/modules/calendar/includes/calendar.views.inc b/sites/all/modules/calendar/includes/calendar.views.inc
index 01a9369..475f73e 100644
--- a/sites/all/modules/calendar/includes/calendar.views.inc
+++ b/sites/all/modules/calendar/includes/calendar.views.inc
@@ -19,6 +19,9 @@ function calendar_views_query_alter(&$view, &$query) {
         $arg = date_pad(date_part_extract($date, 'year'), 4) .'-'. date_pad(date_part_extract($date, 'month'));
         break; 
       case 'week':
+        $ww = date_day_of_week($date, DATE_ISO);
+        $ww = variable_get('date_first_day', 1) ? ($ww == 0 ? 6 : $ww - 1) : $ww;
+        $date = date('Y-m-d', strtotime("-$ww days", strtotime($date)));
         $arg = date_pad(date_part_extract($date, 'year'), 4) .'-W'. date_pad(date_week($date));
         break; 
       default: