Index: location/handlers/location_handler_filter_location_country.inc
===================================================================
--- location/handlers/location_handler_filter_location_country.inc	(revision 707)
+++ location/handlers/location_handler_filter_location_country.inc	(working copy)
@@ -4,7 +4,8 @@
 /**
  * Filter on country.
  */
-class location_handler_filter_location_country extends views_handler_filter {
+//class location_handler_filter_location_country extends views_handler_filter {
+class location_handler_filter_location_country extends views_handler_filter_in_operator {
 
   function option_definition() {
     $options = parent::option_definition();
@@ -25,6 +26,16 @@
    */
   function value_form(&$form, &$form_state) {
     $options = location_get_iso3166_list();
+
+    if (!empty($form_state['exposed'])) {
+      if (!empty($this->options['expose']['reduce'])) {
+        // This code was taken from modules/views/handlers/views_handler_filter_in_operator.inc
+        // I don't think I'm using it correctly, and perhaps instead of extending the 
+        // views_handler_filter_in_operator, we should copy the code into this module.
+        $options = array_intersect_key($options, $this->value);
+      }
+    }
+
     $form['value'] = array(
       '#type' => 'select',
       '#title' => t('Country'),
Index: location/location.views.inc
===================================================================
--- location/location.views.inc	(revision 707)
+++ location/location.views.inc	(working copy)
@@ -37,7 +37,8 @@
         'parent' => 'views_handler_field',
       ),
       'location_handler_filter_location_country' => array(
-        'parent' => 'views_handler_filter',
+        //'parent' => 'views_handler_filter',
+        'parent' => 'views_handler_filter_in_operator',
       ),
       'location_handler_argument_location_country' => array(
         'parent' => 'views_handler_argument',