diff --git a/admin/purgecaches.php b/admin/purgecaches.php
index 006bb0d9768..c2247dc94ec 100644
--- a/admin/purgecaches.php
+++ b/admin/purgecaches.php
@@ -27,37 +27,37 @@ require_once('../config.php');
 require_once($CFG->libdir.'/adminlib.php');
 
 $confirm = optional_param('confirm', 0, PARAM_BOOL);
+$returnurl = optional_param('returnurl', null, PARAM_LOCALURL);
 
+// If we have got here as a confirmed aciton, do it.
+if ($confirm && isloggedin() && confirm_sesskey()) {
+    require_capability('moodle/site:config', context_system::instance());
+
+    // Valid request. Purge, and redirect the user back to where they came from.
+    purge_all_caches();
+
+    if ($returnurl) {
+        $returnurl = $CFG->wwwroot . $returnurl;
+    } else {
+        $returnurl = new moodle_url('/admin/purgecaches.php');
+    }
+    redirect($returnurl, get_string('purgecachesfinished', 'admin'));
+}
+
+// Otherwise, show a button to actually purge the caches.
 admin_externalpage_setup('purgecaches');
 
-require_login();
-require_capability('moodle/site:config', context_system::instance());
-
-if ($confirm) {
-    require_sesskey();
-
-    // Valid request. Purge, and redisplay the form so it is easy to purge again
-    // in the near future.
-    purge_all_caches();
-    redirect(new moodle_url('/admin/purgecaches.php'), get_string('purgecachesfinished', 'admin'));
-
-} else {
-    // Show a confirm form.
-    echo $OUTPUT->header();
-    echo $OUTPUT->heading(get_string('purgecaches', 'admin'));
-
-    $url = new moodle_url('/admin/purgecaches.php', array('sesskey'=>sesskey(), 'confirm'=>1));
-    $button = new single_button($url, get_string('purgecaches','admin'), 'post');
-
-    // Cancel button takes them back to the page the were on, if possible,
-    // otherwise to the site home page.
-    $return = new moodle_url('/');
-    if (isset($_SERVER['HTTP_REFERER']) and !empty($_SERVER['HTTP_REFERER'])) {
-        if ($_SERVER['HTTP_REFERER'] !== "$CFG->wwwroot/$CFG->admin/purgecaches.php") {
-            $return = $_SERVER['HTTP_REFERER'];
-        }
-    }
-
-    echo $OUTPUT->confirm(get_string('purgecachesconfirm', 'admin'), $button, $return);
-    echo $OUTPUT->footer();
+$actionurl = new moodle_url('/admin/purgecaches.php', array('sesskey'=>sesskey(), 'confirm'=>1));
+if ($returnurl) {
+    $actionurl->param('returnurl', $returnurl);
 }
+
+echo $OUTPUT->header();
+echo $OUTPUT->heading(get_string('purgecaches', 'admin'));
+
+echo $OUTPUT->box_start('generalbox', 'notice');
+echo html_writer::tag('p', get_string('purgecachesconfirm', 'admin'));
+echo $OUTPUT->single_button($actionurl, get_string('purgecaches', 'admin'), 'post');
+echo $OUTPUT->box_end();
+
+echo $OUTPUT->footer();
diff --git a/lib/outputrenderers.php b/lib/outputrenderers.php
index 006bf9ab1d6..abdf989324f 100644
--- a/lib/outputrenderers.php
+++ b/lib/outputrenderers.php
@@ -463,7 +463,10 @@ class core_renderer extends renderer_base {
                 $link= '<a title="' . $title . '" href="' . $url . '">' . $txt . '</a>';
                 $output .= '<div class="profilingfooter">' . $link . '</div>';
             }
-            $output .= '<div class="purgecaches"><a href="'.$CFG->wwwroot.'/'.$CFG->admin.'/purgecaches.php?confirm=1&amp;sesskey='.sesskey().'">'.get_string('purgecaches', 'admin').'</a></div>';
+            $purgeurl = new moodle_url('/admin/purgecaches.php', array('confirm' => 1,
+                'sesskey' => sesskey(), 'returnurl' => $this->page->url->out_as_local_url(false)));
+            $output .= '<div class="purgecaches">' .
+                    html_writer::link($purgeurl, get_string('purgecaches', 'admin')) . '</div>';
         }
         if (!empty($CFG->debugvalidators)) {
             // NOTE: this is not a nice hack, $PAGE->url is not always accurate and $FULLME neither, it is not a bug if it fails. --skodak