diff --git a/core/modules/forum/config/forum.yml b/core/modules/forum/config/forum.yml
new file mode 100644
index 0000000..cc10254
--- /dev/null
+++ b/core/modules/forum/config/forum.yml
@@ -0,0 +1,7 @@
+hot_topic: 15
+per_page: 25
+order: 1
+nav_vocabulary: 0
+containers: []
+block_num_active: 5
+block_num_new: 5
\ No newline at end of file
diff --git a/core/modules/forum/forum.admin.inc b/core/modules/forum/forum.admin.inc
index dea573c..454a5bf 100644
--- a/core/modules/forum/forum.admin.inc
+++ b/core/modules/forum/forum.admin.inc
@@ -45,6 +45,7 @@ function forum_form_main($type, $edit = array()) {
  * @ingroup forms
  */
 function forum_form_forum($form, &$form_state, $edit = array()) {
+  $config = config('forum');
   $edit += array(
     'name' => '',
     'description' => '',
@@ -71,7 +72,7 @@ function forum_form_forum($form, &$form_state, $edit = array()) {
     '#description' => t('Forums are displayed in ascending order by weight (forums with equal weights are displayed alphabetically).'),
   );
 
-  $form['vid'] = array('#type' => 'hidden', '#value' => variable_get('forum_nav_vocabulary', ''));
+  $form['vid'] = array('#type' => 'hidden', '#value' => $config->get('nav_vocabulary'));
   $form['actions'] = array('#type' => 'actions');
   $form['actions']['submit'] = array('#type' => 'submit', '#value' => t('Save'));
   if ($edit['tid']) {
@@ -88,6 +89,7 @@ function forum_form_forum($form, &$form_state, $edit = array()) {
  * Form submission handler for forum_form_forum() and forum_form_container().
  */
 function forum_form_submit($form, &$form_state) {
+  $config = config('forum');
   if ($form['form_id']['#value'] == 'forum_form_container') {
     $container = TRUE;
     $type = t('forum container');
@@ -104,9 +106,9 @@ function forum_form_submit($form, &$form_state) {
   switch ($status) {
     case SAVED_NEW:
       if ($container) {
-        $containers = variable_get('forum_containers', array());
+        $containers = $config->get('containers');
         $containers[] = $term->tid;
-        variable_set('forum_containers', $containers);
+        $config->set('containers', $containers);
       }
       $form_state['values']['tid'] = $term->tid;
       drupal_set_message(t('Created new @type %term.', array('%term' => $form_state['values']['name'], '@type' => $type)));
@@ -118,6 +120,7 @@ function forum_form_submit($form, &$form_state) {
       break;
   }
   $form_state['redirect'] = 'admin/structure/forum';
+  $config->save();
   return;
 }
 
@@ -148,6 +151,7 @@ function theme_forum_form($variables) {
  * @ingroup forms
  */
 function forum_form_container($form, &$form_state, $edit = array()) {
+  $config = config('forum');
   $edit += array(
     'name' => '',
     'description' => '',
@@ -181,7 +185,7 @@ function forum_form_container($form, &$form_state, $edit = array()) {
 
   $form['vid'] = array(
     '#type' => 'hidden',
-    '#value' => variable_get('forum_nav_vocabulary', ''),
+    '#value' => $config->get('nav_vocabulary'),
   );
   $form['actions'] = array('#type' => 'actions');
   $form['actions']['submit'] = array(
@@ -235,29 +239,47 @@ function forum_confirm_delete_submit($form, &$form_state) {
  * @see system_settings_form()
  * @ingroup forms
  */
-function forum_admin_settings($form) {
+function forum_admin_settings($form, $form_state) {
+  $config = config('forum');
   $number = drupal_map_assoc(array(5, 10, 15, 20, 25, 30, 35, 40, 50, 60, 80, 100, 150, 200, 250, 300, 350, 400, 500));
-  $form['forum_hot_topic'] = array('#type' => 'select',
+  $form['hot_topic'] = array('#type' => 'select',
     '#title' => t('Hot topic threshold'),
-    '#default_value' => variable_get('forum_hot_topic', 15),
+    '#default_value' => $config->get('hot_topic'),
     '#options' => $number,
     '#description' => t('The number of replies a topic must have to be considered "hot".'),
   );
   $number = drupal_map_assoc(array(10, 25, 50, 75, 100));
-  $form['forum_per_page'] = array('#type' => 'select',
+  $form['per_page'] = array('#type' => 'select',
     '#title' => t('Topics per page'),
-    '#default_value' => variable_get('forum_per_page', 25),
+    '#default_value' => $config->get('per_page'),
     '#options' => $number,
     '#description' => t('Default number of forum topics displayed per page.'),
   );
   $forder = array(1 => t('Date - newest first'), 2 => t('Date - oldest first'), 3 => t('Posts - most active first'), 4 => t('Posts - least active first'));
-  $form['forum_order'] = array('#type' => 'radios',
+  $form['order'] = array('#type' => 'radios',
     '#title' => t('Default order'),
-    '#default_value' => variable_get('forum_order', 1),
+    '#default_value' => $config->get('order'),
     '#options' => $forder,
     '#description' => t('Default display order for topics.'),
   );
-  return system_settings_form($form);
+  return system_config_form($form, $form_state);
+}
+
+
+/**
+ * Form submission handler for forum_admin_settings().
+ *
+ * @see forum_admin_settings()
+ */
+function forum_admin_settings_submit($form, &$form_state) {
+  $config = config('forum');
+  $config_items = array('hot_topic', 'per_page', 'order');
+  foreach ($config_items as $config_item) {
+    if ($config->get($config_item) != $form_state['values'][$config_item]) {
+      $config-set($config_item, $form_state['values'][$config_item]);
+    }
+  }
+  $config->save();
 }
 
 /**
@@ -271,8 +293,9 @@ function forum_admin_settings($form) {
  */
 function forum_overview($form, &$form_state) {
   module_load_include('inc', 'taxonomy', 'taxonomy.admin');
+  $config = config('forum');
 
-  $vid = variable_get('forum_nav_vocabulary', '');
+  $vid = $config->get('nav_vocabulary');
   $vocabulary = taxonomy_vocabulary_load($vid);
   $form = taxonomy_overview_terms($form, $form_state, $vocabulary);
 
@@ -281,7 +304,7 @@ function forum_overview($form, &$form_state) {
       $term = $form[$key]['#term'];
       $form[$key]['view']['#href'] = 'forum/' . $term['tid'];
       unset($form[$key]['operations']['#links']['delete']);
-      if (in_array($form[$key]['#term']['tid'], variable_get('forum_containers', array()))) {
+      if (in_array($form[$key]['#term']['tid'], $config->get('containers'))) {
         $form[$key]['operations']['#links']['edit']['title'] = t('edit container');
         $form[$key]['operations']['#links']['edit']['href'] = 'admin/structure/forum/edit/container/' . $term['tid'];
       }
@@ -316,7 +339,6 @@ function forum_overview($form, &$form_state) {
  *   A select form element.
  */
 function _forum_parent_select($tid, $title, $child_type) {
-
   $parents = taxonomy_term_load_parents($tid);
   if ($parents) {
     $parent = array_shift($parents);
@@ -326,7 +348,7 @@ function _forum_parent_select($tid, $title, $child_type) {
     $parent = 0;
   }
 
-  $vid = variable_get('forum_nav_vocabulary', '');
+  $vid = config('forum')->get('nav_vocabulary');
   $children = taxonomy_get_tree($vid, $tid);
 
   // A term can't be the child of itself, nor of its children.
diff --git a/core/modules/forum/forum.install b/core/modules/forum/forum.install
index fb1ba4c..6d159d6 100644
--- a/core/modules/forum/forum.install
+++ b/core/modules/forum/forum.install
@@ -16,6 +16,7 @@ function forum_install() {
     ->execute();
   // Forum topics are published by default, but do not have any other default
   // options set (for example, they are not promoted to the front page).
+  // @todo convert this to use cmi once node module does.
   variable_set('node_options_forum', array('status'));
 }
 
@@ -28,7 +29,8 @@ function forum_enable() {
   // hook modules_enabled is called which takes place after hook_enable events.
   field_associate_fields('taxonomy');
   // Create the forum vocabulary if it does not exist.
-  $vocabulary = taxonomy_vocabulary_load(variable_get('forum_nav_vocabulary', 0));
+  $config = config('forum');
+  $vocabulary = taxonomy_vocabulary_load($config->get('nav_vocabulary'));
   if (!$vocabulary) {
     $vocabulary = entity_create('taxonomy_vocabulary', array(
       'name' => t('Forums'),
@@ -40,7 +42,8 @@ function forum_enable() {
       'weight' => -10,
     ));
     taxonomy_vocabulary_save($vocabulary);
-    variable_set('forum_nav_vocabulary', $vocabulary->vid);
+    $config->set('nav_vocabulary', $vocabulary->vid);
+    $config->save();
   }
 
   // Create the 'taxonomy_forums' field if it doesn't already exist.
@@ -106,14 +109,6 @@ function forum_uninstall() {
   // Load the dependent Taxonomy module, in case it has been disabled.
   drupal_load('module', 'taxonomy');
 
-  variable_del('forum_containers');
-  variable_del('forum_hot_topic');
-  variable_del('forum_per_page');
-  variable_del('forum_order');
-  variable_del('forum_block_num_active');
-  variable_del('forum_block_num_new');
-  variable_del('node_options_forum');
-
   field_delete_field('taxonomy_forums');
   // Purge field data now to allow taxonomy module to be uninstalled
   // if this is the only field remaining.
@@ -246,3 +241,19 @@ function forum_schema() {
 function forum_update_last_removed() {
   return 7003;
 }
+
+/**
+ * Update forum module to use the configuration system.
+ */
+function forum_update_8000() {
+  config_install_default_config('forum');
+  update_variables_to_config('forum', array(
+    'forum_hot_topic' => 'hot_topic',
+    'forum_per_page' => 'per_page',
+    'forum_order' => 'order',
+    'forum_nav_vocabulary' => 'nav_vocabulary',
+    'forum_containers' => 'containers',
+    'forum_block_num_active' => 'block_num_active',
+    'forum_block_num_new' => 'block_num_new',
+  ));
+}
diff --git a/core/modules/forum/forum.module b/core/modules/forum/forum.module
index ca9bf7e..e09db09 100644
--- a/core/modules/forum/forum.module
+++ b/core/modules/forum/forum.module
@@ -219,7 +219,7 @@ function forum_menu_local_tasks_alter(&$data, $router_item, $root_path) {
  */
 function forum_entity_info_alter(&$info) {
   // Take over URI construction for taxonomy terms that are forums.
-  if ($vid = variable_get('forum_nav_vocabulary', 0)) {
+  if ($vid = config('forum')->get('nav_vocabulary')) {
     // Within hook_entity_info(), we can't invoke entity_load() as that would
     // cause infinite recursion, so we call taxonomy_vocabulary_get_names()
     // instead of taxonomy_vocabulary_load(). All we need is the machine name
@@ -264,7 +264,7 @@ function _forum_node_check_node_type(Node $node) {
  * Implements hook_node_view().
  */
 function forum_node_view(Node $node, $view_mode) {
-  $vid = variable_get('forum_nav_vocabulary', 0);
+  $vid = config('forum')->get('nav_vocabulary');
   $vocabulary = taxonomy_vocabulary_load($vid);
   if (_forum_node_check_node_type($node)) {
     if ($view_mode == 'full' && node_is_page($node)) {
@@ -295,7 +295,7 @@ function forum_node_validate(Node $node, $form) {
     // vocabulary is selected, not a "container" term.
     if (!empty($node->taxonomy_forums[$langcode])) {
       // Extract the node's proper topic ID.
-      $containers = variable_get('forum_containers', array());
+      $containers = config('forum')->get('containers');
       foreach ($node->taxonomy_forums[$langcode] as $delta => $item) {
         // If no term was selected (e.g. when no terms exist yet), remove the
         // item.
@@ -474,12 +474,14 @@ function forum_permission() {
  */
 function forum_taxonomy_term_delete(Term $term) {
   // For containers, remove the tid from the forum_containers variable.
-  $containers = variable_get('forum_containers', array());
+  $config = config('forum');
+  $containers = $config->get('containers');
   $key = array_search($term->tid, $containers);
   if ($key !== FALSE) {
     unset($containers[$key]);
   }
-  variable_set('forum_containers', $containers);
+  $config->set('containers', $containers);
+  $config->save();
 }
 
 /**
@@ -593,7 +595,7 @@ function forum_field_storage_pre_update($entity_type, $entity, &$skip_fields) {
  * Implements hook_form_FORM_ID_alter() for taxonomy_form_vocabulary().
  */
 function forum_form_taxonomy_form_vocabulary_alter(&$form, &$form_state, $form_id) {
-  $vid = variable_get('forum_nav_vocabulary', 0);
+  $vid = config('forum')->get('nav_vocabulary');
   if (isset($form['vid']['#value']) && $form['vid']['#value'] == $vid) {
     $form['help_forum_vocab'] = array(
       '#markup' => t('This is the designated forum vocabulary. Some of the normal vocabulary options have been removed.'),
@@ -612,7 +614,7 @@ function forum_form_taxonomy_form_vocabulary_alter(&$form, &$form_state, $form_i
  * Implements hook_form_FORM_ID_alter() for taxonomy_form_term().
  */
 function forum_form_taxonomy_form_term_alter(&$form, &$form_state, $form_id) {
-  $vid = variable_get('forum_nav_vocabulary', 0);
+  $vid = config('forum')->get('nav_vocabulary');
   if (isset($form['vid']['#value']) && $form['vid']['#value'] == $vid) {
     // Hide multiple parents select from forum terms.
     $form['relations']['parent']['#access'] = FALSE;
@@ -659,7 +661,7 @@ function forum_block_info() {
  * Implements hook_block_configure().
  */
 function forum_block_configure($delta = '') {
-  $form['forum_block_num_' . $delta] = array('#type' => 'select', '#title' => t('Number of topics'), '#default_value' => variable_get('forum_block_num_' . $delta, '5'), '#options' => drupal_map_assoc(array(2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20)));
+  $form['block_num_' . $delta] = array('#type' => 'select', '#title' => t('Number of topics'), '#default_value' => config('forum')->get('block_num_' . $delta), '#options' => drupal_map_assoc(array(2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20)));
   return $form;
 }
 
@@ -667,7 +669,9 @@ function forum_block_configure($delta = '') {
  * Implements hook_block_save().
  */
 function forum_block_save($delta = '', $edit = array()) {
-  variable_set('forum_block_num_' . $delta, $edit['forum_block_num_' . $delta]);
+  $config = config('forum');
+  $config->set('block_num_' . $delta, $edit['block_num_' . $delta]);
+  $config->save();
 }
 
 /**
@@ -677,6 +681,7 @@ function forum_block_save($delta = '', $edit = array()) {
  * recently added forum topics.
  */
 function forum_block_view($delta = '') {
+  $config = config('forum');
   $query = db_select('forum_index', 'f')
     ->fields('f')
     ->addTag('node_access');
@@ -685,14 +690,14 @@ function forum_block_view($delta = '') {
       $title = t('Active forum topics');
       $query
         ->orderBy('f.last_comment_timestamp', 'DESC')
-        ->range(0, variable_get('forum_block_num_active', '5'));
+        ->range(0, $config->get('block_num_active'));
       break;
 
     case 'new':
       $title = t('New forum topics');
       $query
         ->orderBy('f.created', 'DESC')
-        ->range(0, variable_get('forum_block_num_new', '5'));
+        ->range(0, $config->get('block_num_new'));
       break;
   }
 
@@ -767,7 +772,8 @@ function forum_forum_load($tid = NULL) {
     return $cache[$tid];
   }
 
-  $vid = variable_get('forum_nav_vocabulary', 0);
+  $config = config('forum');
+  $vid = $config->get('nav_vocabulary');
 
   // Load and validate the parent term.
   if ($tid) {
@@ -784,7 +790,7 @@ function forum_forum_load($tid = NULL) {
   }
 
   // Determine if the requested term is a container.
-  if (!$forum_term->tid || in_array($forum_term->tid, variable_get('forum_containers', array()))) {
+  if (!$forum_term->tid || in_array($forum_term->tid, $config->get('containers'))) {
     $forum_term->container = 1;
   }
 
@@ -812,7 +818,7 @@ function forum_forum_load($tid = NULL) {
 
   foreach ($_forums as $forum) {
     // Determine if the child term is a container.
-    if (in_array($forum->tid, variable_get('forum_containers', array()))) {
+    if (in_array($forum->tid, $config->get('containers'))) {
       $forum->container = 1;
     }
 
@@ -1056,7 +1062,8 @@ function forum_preprocess_block(&$variables) {
 function template_preprocess_forums(&$variables) {
   global $user;
 
-  $vid = variable_get('forum_nav_vocabulary', 0);
+  $config = config('forum');
+  $vid = $config->get('nav_vocabulary');
   $vocabulary = taxonomy_vocabulary_load($vid);
   $title = !empty($vocabulary->name) ? $vocabulary->name : '';
 
@@ -1087,7 +1094,7 @@ function template_preprocess_forums(&$variables) {
       $variables['forums'] = '';
     }
 
-    if ($variables['tid'] && !in_array($variables['tid'], variable_get('forum_containers', array()))) {
+    if ($variables['tid'] && !in_array($variables['tid'], $config->get('containers'))) {
       $variables['topics'] = theme('forum_topic_list', $variables);
       drupal_add_feed('taxonomy/term/' . $variables['tid'] . '/feed', 'RSS - ' . $title);
     }
@@ -1251,7 +1258,7 @@ function template_preprocess_forum_topic_list(&$variables) {
  * @see theme_forum_icon()
  */
 function template_preprocess_forum_icon(&$variables) {
-  $variables['hot_threshold'] = variable_get('forum_hot_topic', 15);
+  $variables['hot_threshold'] = config('forum')->get('hot_topic');
   if ($variables['num_posts'] > $variables['hot_threshold']) {
     $variables['icon_class'] = $variables['new_posts'] ? 'hot-new' : 'hot';
     $variables['icon_title'] = $variables['new_posts'] ? t('Hot topic, new comments') : t('Hot topic');
diff --git a/core/modules/forum/forum.pages.inc b/core/modules/forum/forum.pages.inc
index 8538310..12da66a 100644
--- a/core/modules/forum/forum.pages.inc
+++ b/core/modules/forum/forum.pages.inc
@@ -18,13 +18,14 @@
  * @see forum_menu()
  */
 function forum_page($forum_term = NULL) {
+  $config = config('forum');
   if (!isset($forum_term)) {
     // On the main page, display all the top-level forums.
     $forum_term = forum_forum_load(0);
   }
 
-  $forum_per_page = variable_get('forum_per_page', 25);
-  $sortby = variable_get('forum_order', 1);
+  $forum_per_page = $config->get('per_page');
+  $sortby = $config->get('order');
 
   if (empty($forum_term->container)) {
     $topics = forum_get_topics($forum_term->tid, $sortby, $forum_per_page);
diff --git a/core/modules/forum/lib/Drupal/forum/Tests/ForumTest.php b/core/modules/forum/lib/Drupal/forum/Tests/ForumTest.php
index 14a4c7b..3143540 100644
--- a/core/modules/forum/lib/Drupal/forum/Tests/ForumTest.php
+++ b/core/modules/forum/lib/Drupal/forum/Tests/ForumTest.php
@@ -215,7 +215,7 @@ class ForumTest extends WebTestBase {
    */
   function testAddOrphanTopic() {
     // Must remove forum topics to test creating orphan topics.
-    $vid = variable_get('forum_nav_vocabulary');
+    $vid = config('forum')->get('nav_vocabulary');
     $tree = taxonomy_get_tree($vid);
     foreach ($tree as $term) {
       taxonomy_term_delete($term->tid);
@@ -329,7 +329,7 @@ class ForumTest extends WebTestBase {
    */
   function editForumTaxonomy() {
     // Backup forum taxonomy.
-    $vid = variable_get('forum_nav_vocabulary', '');
+    $vid = config('forum')->get('nav_vocabulary');
     $original_settings = taxonomy_vocabulary_load($vid);
 
     // Generate a random name/description.
@@ -392,7 +392,7 @@ class ForumTest extends WebTestBase {
     $this->assertRaw(t('Created new @type %term.', array('%term' => $name, '@type' => t($type))), t(ucfirst($type) . ' was created'));
 
     // Verify forum.
-    $term = db_query("SELECT * FROM {taxonomy_term_data} t WHERE t.vid = :vid AND t.name = :name AND t.description = :desc", array(':vid' => variable_get('forum_nav_vocabulary', ''), ':name' => $name, ':desc' => $description))->fetchAssoc();
+    $term = db_query("SELECT * FROM {taxonomy_term_data} t WHERE t.vid = :vid AND t.name = :name AND t.description = :desc", array(':vid' => config('forum')->get('nav_vocabulary'), ':name' => $name, ':desc' => $description))->fetchAssoc();
     $this->assertTrue(!empty($term), 'The ' . $type . ' exists in the database');
 
     // Verify forum hierarchy.
@@ -420,7 +420,7 @@ class ForumTest extends WebTestBase {
 
     // Assert that the associated term has been removed from the
     // forum_containers variable.
-    $containers = variable_get('forum_containers', array());
+    $containers = config('forum')->get('containers');
     $this->assertFalse(in_array($tid, $containers), 'The forum_containers variable has been updated.');
   }