diff --git a/core/includes/install.inc b/core/includes/install.inc
index 67e41f66225b8d8247f9c00424109b922c5875ce..176e941fbf4d9d2d15c56b47cd80c4fb7bce31a5 100644
--- a/core/includes/install.inc
+++ b/core/includes/install.inc
@@ -503,10 +503,10 @@ function drupal_install_config_directories() {
     // to the drupal core repo.
     switch ($config_type) {
       case CONFIG_ACTIVE_DIRECTORY:
-        $text = 'This directory contains the active configuration for your Drupal site. To move this configuration between environments, contents from this directory should be placed in the staging directory on the target server. To make this configuration active, see admin/config/development/configuration/sync on the target server.';
+        $text = 'If you change the configuration system to use file storage instead of the database for the active Drupal site configuration, this directory will contain the active configuration. By default, this directory will be empty. If you are using files to store the active configuration, and you want to move it between environments, files from this directory should be placed in the staging directory on the target server. To make this configuration active, visit admin/config/development/configuration/sync on the target server.';
         break;
       case CONFIG_STAGING_DIRECTORY:
-        $text = 'This directory contains configuration to be imported into your Drupal site. To make this configuration active, see admin/config/development/configuration/sync.';
+        $text = 'This directory contains configuration to be imported into your Drupal site. To make this configuration active, visit admin/config/development/configuration/sync.';
         break;
     }
     $text .=  ' For information about deploying configuration between servers, see http://drupal.org/documentation/administer/config';
diff --git a/sites/default/default.settings.php b/sites/default/default.settings.php
index 334c18602d3d3178c57f6e95168cf5baa2eb4c6f..e9b4b4706d6c9b60045d4e530cc1297e64d7dfe0 100644
--- a/sites/default/default.settings.php
+++ b/sites/default/default.settings.php
@@ -221,12 +221,18 @@
 /**
  * Location of the site configuration files.
  *
- * By default, Drupal configuration files are stored in a randomly named
- * directory under the default public files path. On install the
- * named directory is created in the default files directory. For enhanced
- * security, you may set this variable to a location outside your docroot.
- *
- * @todo Flesh this out, provide more details, etc.
+ * The $config_directories array specifies the location of file system
+ * directories used for configuration data. On install, "active" and "staging"
+ * directories are created for configuration. The staging directory is used for
+ * configuration imports; the active directory is not used by default, since the
+ * default storage for active configuration is the database rather than the file
+ * system (this can be changed; see "Active configuration settings" below).
+ *
+ * The default location for the active and staging directories is inside a
+ * randomly-named directory in the public files path; this setting allows you to
+ * override these locations. If you use files for the active configuration, you
+ * can enhance security by putting the active configuration outside your
+ * document root.
  *
  * Example:
  * @code
@@ -256,9 +262,9 @@
  * site is deployed on a cluster of web servers, you must ensure that this
  * variable has the same value on each server.
  *
- * For enhanced security, you may set this variable to a value using the
- * contents of a file outside your docroot that is never saved together
- * with any backups of your Drupal files and database.
+ * For enhanced security, you may set this variable to the contents of a file
+ * outside your document root; you should also ensure that this file is not
+ * stored with backups of your database.
  *
  * Example:
  * @code
@@ -546,12 +552,14 @@
  * Active configuration settings.
  *
  * By default, the active configuration is stored in the database in the
- * {config} table. To install Drupal with a different active configuration
- * storage, you need to override the setting here, in addition to overriding
- * the config.storage.active service definition in a module or profile.
- *
- * The 'bootstrap_config_storage' setting needs to be a callable that returns
- * core.services.yml.
+ * {config} table. To use a different storage mechanism for the active
+ * configuration, do the following prior to installing:
+ * - Override the 'bootstrap_config_storage' setting here. It must be set to a
+ *   callable that returns an object that implements
+ *   \Drupal\Core\Config\StorageInterface.
+ * - Override the service definition 'config.storage.active'. Put this
+ *   override in a services.yml file in the same directory as settings.php
+ *   (definitions in this file will override service definition defaults).
  */
 # $settings['bootstrap_config_storage'] = array('Drupal\Core\Config\BootstrapConfigStorageFactory', 'getFileStorage');