diff --git a/core/includes/install.core.inc b/core/includes/install.core.inc
index d75ed9f..7a46d2e 100644
--- a/core/includes/install.core.inc
+++ b/core/includes/install.core.inc
@@ -439,6 +439,13 @@ function install_begin_request($class_loader, &$install_state) {
     if (isset($install_state['profile_info']['distribution']['install']['theme'])) {
       $install_state['theme'] = $install_state['profile_info']['distribution']['install']['theme'];
     }
+    // Ensure all profile directories are registered.
+    $profile_dependencies = $listing->getProfileDependencies($profile);
+    $profile_directories = array();
+    foreach ($profile_dependencies as $profile_dependency => $profile_dependency_info) {
+      $profile_directories[] = drupal_get_path('profile', $profile_dependency);
+    }
+    $listing->setProfileDirectories($profile_directories);
   }
 
   // Use the language from the profile configuration, if available, to override
@@ -1550,6 +1557,13 @@ function install_profile_themes(&$install_state) {
  *   An array of information about the current installation state.
  */
 function install_install_profile(&$install_state) {
+  // Install base profiles first.
+  foreach ($install_state['profile_info']['base_profiles'] as $base_profile) {
+    \Drupal::service('module_installer')->install(array($base_profile), FALSE);
+    //\Drupal::service('config.installer')->installOptionalConfig();
+  }
+
+  // Now install the profile.
   \Drupal::service('module_installer')->install(array(drupal_get_profile()), FALSE);
   // Install all available optional config. During installation the module order
   // is determined by dependencies. If there are no dependencies between modules
@@ -2182,6 +2196,16 @@ function install_write_profile($install_state) {
       'value' => $install_state['parameters']['profile'],
       'required' => TRUE,
     );
+  }
+  // Add specified base_profile to the settings profile_directories.
+  if (!empty($install_state['profile_info']['base_profile']['name']) && isset($install_state['profiles'][$install_state['profile_info']['base_profile']['name']]) && empty(Settings::get('profile_directories'))) {
+    $path = $install_state['profiles'][$install_state['profile_info']['base_profile']['name']]->getPath();
+    $settings['settings']['profile_directories'] = (object) array(
+      'value' => array($path),
+      'required' => TRUE,
+    );
+  }
+  if (!empty($settings)) {
     drupal_rewrite_settings($settings);
   }
 }
diff --git a/core/includes/install.inc b/core/includes/install.inc
index 61725da..6612d2f 100644
--- a/core/includes/install.inc
+++ b/core/includes/install.inc
@@ -11,6 +11,7 @@
 use Drupal\Component\Utility\OpCodeCache;
 use Drupal\Component\Utility\UrlHelper;
 use Drupal\Core\Extension\ExtensionDiscovery;
+use Drupal\Core\Extension\ModuleHandler;
 use Drupal\Core\Site\Settings;
 
 /**
@@ -1012,6 +1013,8 @@ function drupal_check_module($module) {
  * - description: A brief description of the profile.
  * - dependencies: An array of shortnames of other modules that this install
  *   profile requires.
+ * - base_profiles: An array of shortnames of other profiles this install
+ *   profile depends on.
  *
  * Additional, less commonly-used information that can appear in a
  * profile.info.yml file but not in a normal Drupal module .info.yml file
@@ -1029,6 +1032,12 @@ function drupal_check_module($module) {
  *   - install: Optional parameters to override the installer:
  *     - theme: The machine name of a theme to use in the installer instead of
  *       Drupal's default installer theme.
+ * - base_profile: Existence of this key denotes that the installation profile
+ *   depends on a parent installation profile.
+ *   - name: The shortname of the base installation profile.
+ *   - excluded_dependencies: An array of shortnames of other modules that have
+ *     to be excluded from the base profile requirements. This allows e.g. to
+ *     disable a demo module that would be installed by the base profile.
  *
  * Note that this function does an expensive file system scan to get info file
  * information for dependencies. If you only need information from the info
@@ -1062,6 +1071,7 @@ function install_profile_info($profile, $langcode = 'en') {
       'version' => NULL,
       'hidden' => FALSE,
       'php' => DRUPAL_MINIMUM_PHP,
+      'base_profiles' => array(),
     );
     $profile_file = drupal_get_path('profile', $profile) . "/$profile.info.yml";
     $info = \Drupal::service('info_parser')->parse($profile_file);
@@ -1073,6 +1083,27 @@ function install_profile_info($profile, $langcode = 'en') {
 
     $locale = !empty($langcode) && $langcode != 'en' ? array('locale') : array();
 
+    // Get the base profile chain.
+    if (!empty($info['base_profile']['name'])) {
+      $info['base_profiles'][$info['base_profile']['name']] = $info['base_profile']['name'];
+      $base_profile = install_profile_info($info['base_profile']['name'], $langcode);
+      $info['base_profiles'] += $base_profile['base_profiles'];
+
+      // Ensure all dependencies are cleanly merged.
+      $info['dependencies'] = array_merge($info['dependencies'], $base_profile['dependencies']);
+      // If there are dependency excludes from the base apply them now.
+      if (!empty($info['base_profile']['excluded_dependencies'])) {
+        $info['dependencies'] = array_diff($info['dependencies'], $info['base_profile']['excluded_dependencies']);
+      }
+      // Ensure there's no circular dependency.
+      $info['dependencies'] = array_diff($info['dependencies'], array($profile));
+    }
+
+    // Ensure the same dependency notation as in modules can be used.
+    array_walk($info['dependencies'], function(&$dependency) {
+      $dependency = ModuleHandler::parseDependency($dependency)['name'];
+    });
+
     $info['dependencies'] = array_unique(array_merge($required, $info['dependencies'], $locale));
 
     $cache[$profile][$langcode] = $info;
diff --git a/core/lib/Drupal/Core/Config/ConfigInstaller.php b/core/lib/Drupal/Core/Config/ConfigInstaller.php
index cc0d88f..612d545 100644
--- a/core/lib/Drupal/Core/Config/ConfigInstaller.php
+++ b/core/lib/Drupal/Core/Config/ConfigInstaller.php
@@ -462,7 +462,7 @@ public function checkConfigurationToInstall($type, $name) {
 
     // Install profiles can not have config clashes. Configuration that
     // has the same name as a module's configuration will be used instead.
-    if ($name != $this->drupalGetProfile()) {
+    if ($name != $this->drupalGetProfile() && !in_array($name, $this->drupalGetBaseProfiles())) {
       // Throw an exception if the module being installed contains configuration
       // that already exists. Additionally, can not continue installing more
       // modules because those may depend on the current module being installed.
@@ -646,6 +646,20 @@ protected function drupalGetProfile() {
   }
 
   /**
+   * Gets the base profiles of the install profile.
+   *
+   * @return array $profile
+   *   The list of base profile names the currently installed profile depends
+   *   on.
+   */
+  protected function drupalGetBaseProfiles() {
+    $profile = $this->drupalGetProfile();
+    include_once DRUPAL_ROOT . '/core/includes/install.inc';
+    $profile_info = install_profile_info($profile);
+    return $profile_info['base_profiles'];
+  }
+
+  /**
    * Wrapper for drupal_installation_attempted().
    *
    * @return bool
diff --git a/core/lib/Drupal/Core/DrupalKernel.php b/core/lib/Drupal/Core/DrupalKernel.php
index 1a3b943..377ec18 100644
--- a/core/lib/Drupal/Core/DrupalKernel.php
+++ b/core/lib/Drupal/Core/DrupalKernel.php
@@ -718,6 +718,10 @@ protected function moduleData($module) {
       $profile_directories = array_map(function ($profile) {
         return $profile->getPath();
       }, $profiles);
+
+      // Allow additional profile directories to be added from settings.php.
+      // This provides support for "base profiles".
+      $profile_directories = array_merge(Settings::get('profile_directories', []), $profile_directories);
       $listing->setProfileDirectories($profile_directories);
 
       // Now find modules.
diff --git a/core/lib/Drupal/Core/Extension/ExtensionDiscovery.php b/core/lib/Drupal/Core/Extension/ExtensionDiscovery.php
index 337629b..9690fbd 100644
--- a/core/lib/Drupal/Core/Extension/ExtensionDiscovery.php
+++ b/core/lib/Drupal/Core/Extension/ExtensionDiscovery.php
@@ -16,6 +16,14 @@
  * $settings['extension_discovery_scan_tests'] = TRUE;
  * @endcode
  * to your settings.php.
+ *
+ * To add additional profile directories, add
+ * @code
+ * $settings['profile_directories'] = array(path);
+ * @encode
+ * to your settings.php.  If multiple paths are specified, they are searched
+ * from last to first.
+ *
  */
 class ExtensionDiscovery {
 
@@ -248,8 +256,15 @@ public function setProfileDirectoriesFromSettings() {
     // In case both profile directories contain the same extension, the actual
     // profile always has precedence.
     if ($profile) {
-      $this->profileDirectories[] = drupal_get_path('profile', $profile);
+      foreach ($this->getProfileDependencies($profile) as $profile_dependency => $profile_dependency_info) {
+        $this->profileDirectories[] = drupal_get_path('profile', $profile_dependency);
+      }
     }
+
+    // Allow additional profile directories to be added from settings.php.
+    // This provides support for "base profiles".
+    $this->profileDirectories = array_merge(Settings::get('profile_directories', []), $this->profileDirectories);
+
     return $this;
   }
 
@@ -265,6 +280,40 @@ public function getProfileDirectories() {
   }
 
   /**
+   * Returns a list of related installation profiles.
+   *
+   * @param $profile
+   *   Name of profile.
+   *
+   * @return array
+   *   List of dependent installation profiles in descending order of their
+   *   dependencies.
+   */
+  public function getProfileDependencies($profile) {
+    $cache = &drupal_static(__FUNCTION__, array());
+    if (!isset($cache[$profile])) {
+      $profiles = array();
+      // Check if a valid profile name was given.
+      if (!empty($profile)) {
+        // We can't use install_profile_info() because that could trigger an
+        // endless loop. So we read this on our own.
+        $profile_file = drupal_get_path('profile', $profile) . "/$profile.info.yml";
+        $profile_info = \Drupal::service('info_parser')->parse($profile_file);
+
+        // Check of the profile has a base profile and if so add it - recursion.
+        // @TODO do we need a endless-loop protection?
+        if (!empty($profile_info['base_profile']['name'])) {
+          $profiles += $this->getProfileDependencies($profile_info['base_profile']['name']);
+        }
+        // Add requested profile as last one.
+        $profiles[$profile] = $profile;
+      }
+      $cache[$profile] = $profiles;
+    }
+    return $cache[$profile];
+  }
+
+  /**
    * Sets explicit profile directories to scan.
    *
    * @param array $paths