diff --git a/core/modules/config/src/Tests/ConfigSchemaTest.php b/core/modules/config/src/Tests/ConfigSchemaTest.php
index fae3923..5dbec35 100644
--- a/core/modules/config/src/Tests/ConfigSchemaTest.php
+++ b/core/modules/config/src/Tests/ConfigSchemaTest.php
@@ -166,6 +166,9 @@ function testSchemaMapping() {
     $expected['mapping']['effects']['sequence'][0]['mapping']['data']['type'] = 'image.effect.[%parent.id]';
     $expected['mapping']['effects']['sequence'][0]['mapping']['weight']['type'] = 'integer';
     $expected['mapping']['effects']['sequence'][0]['mapping']['uuid']['type'] = 'string';
+    $expected['mapping']['third_party_settings']['type'] = 'sequence';
+    $expected['mapping']['third_party_settings']['label'] = 'Third party settings';
+    $expected['mapping']['third_party_settings']['sequence'][0]['type'] = 'image_style.third_party.[%key]';
     $expected['type'] = 'image.style.*';
 
     $this->assertEqual($definition, $expected);
diff --git a/core/modules/image/config/schema/image.schema.yml b/core/modules/image/config/schema/image.schema.yml
index 4f1fc79..88075cf 100644
--- a/core/modules/image/config/schema/image.schema.yml
+++ b/core/modules/image/config/schema/image.schema.yml
@@ -22,6 +22,11 @@ image.style.*:
               type: integer
             uuid:
               type: string
+    third_party_settings:
+      type: sequence
+      label: 'Third party settings'
+      sequence:
+        - type: image_style.third_party.[%key]
 
 image.effect.image_crop:
   type: image_size
diff --git a/core/modules/image/src/Entity/ImageStyle.php b/core/modules/image/src/Entity/ImageStyle.php
index 4506891..2e77f7f 100644
--- a/core/modules/image/src/Entity/ImageStyle.php
+++ b/core/modules/image/src/Entity/ImageStyle.php
@@ -9,6 +9,7 @@
 
 use Drupal\Core\Cache\Cache;
 use Drupal\Core\Config\Entity\ConfigEntityBase;
+use Drupal\Core\Config\Entity\ThirdPartySettingsTrait;
 use Drupal\Core\Entity\EntityStorageInterface;
 use Drupal\Core\Entity\EntityWithPluginBagsInterface;
 use Drupal\Core\Routing\RequestHelper;
@@ -50,6 +51,8 @@
  */
 class ImageStyle extends ConfigEntityBase implements ImageStyleInterface, EntityWithPluginBagsInterface {
 
+  use ThirdPartySettingsTrait;
+
   /**
    * The name of the image style to use as replacement upon delete.
    *
diff --git a/core/modules/image/src/ImageStyleInterface.php b/core/modules/image/src/ImageStyleInterface.php
index fa14faf..7475b03 100644
--- a/core/modules/image/src/ImageStyleInterface.php
+++ b/core/modules/image/src/ImageStyleInterface.php
@@ -8,11 +8,12 @@
 namespace Drupal\image;
 
 use Drupal\Core\Config\Entity\ConfigEntityInterface;
+use Drupal\Core\Config\Entity\ThirdPartySettingsInterface;
 
 /**
  * Provides an interface defining an image style entity.
  */
-interface ImageStyleInterface extends ConfigEntityInterface {
+interface ImageStyleInterface extends ConfigEntityInterface, ThirdPartySettingsInterface {
 
   /**
    * Returns the replacement ID.
diff --git a/core/modules/image/src/Tests/ImageAdminStylesTest.php b/core/modules/image/src/Tests/ImageAdminStylesTest.php
index d998883..5487078 100644
--- a/core/modules/image/src/Tests/ImageAdminStylesTest.php
+++ b/core/modules/image/src/Tests/ImageAdminStylesTest.php
@@ -124,6 +124,12 @@ function testStyle() {
 
     // Load the saved image style.
     $style = entity_load('image_style', $style_name);
+
+    // Ensure that third party settings were added to the config entity.
+    // These are added by a hook_image_style_presave() implemented in
+    // image_module_test module.
+    $this->assertEqual('bar', $style->getThirdPartySetting('image_module_test', 'foo'), 'Third party settings were added to the image style.');
+
     // Ensure that the image style URI matches our expected path.
     $style_uri_path = $style->url();
     $this->assertTrue(strpos($style_uri_path, $style_path) !== FALSE, 'The image style URI is correct.');
diff --git a/core/modules/image/src/Tests/ImageFieldTestBase.php b/core/modules/image/src/Tests/ImageFieldTestBase.php
index 561737a..64b912e 100644
--- a/core/modules/image/src/Tests/ImageFieldTestBase.php
+++ b/core/modules/image/src/Tests/ImageFieldTestBase.php
@@ -32,7 +32,7 @@
    *
    * @var array
    */
-  public static $modules = array('node', 'image', 'field_ui');
+  public static $modules = array('node', 'image', 'field_ui', 'image_module_test');
 
   protected $admin_user;
 
diff --git a/core/modules/image/tests/modules/image_module_test/config/schema/image_module_test.schema.yml b/core/modules/image/tests/modules/image_module_test/config/schema/image_module_test.schema.yml
new file mode 100644
index 0000000..a36719d
--- /dev/null
+++ b/core/modules/image/tests/modules/image_module_test/config/schema/image_module_test.schema.yml
@@ -0,0 +1,7 @@
+image_style.third_party.image_module_test:
+  type: mapping
+  label: 'Schema for image_module_test module additions to image_style entity'
+  mapping:
+    foo:
+      type: string
+      label: 'Label for foo'
diff --git a/core/modules/image/tests/modules/image_module_test/image_module_test.module b/core/modules/image/tests/modules/image_module_test/image_module_test.module
index 0242f1e..df71375 100644
--- a/core/modules/image/tests/modules/image_module_test/image_module_test.module
+++ b/core/modules/image/tests/modules/image_module_test/image_module_test.module
@@ -5,6 +5,8 @@
  * Provides Image module hook implementations for testing purposes.
  */
 
+use Drupal\image\ImageStyleInterface;
+
 function image_module_test_file_download($uri) {
   $default_uri = \Drupal::state()->get('image.test_file_download') ?: FALSE;
   if ($default_uri == $uri) {
@@ -21,3 +23,12 @@ function image_module_test_image_effect_info_alter(&$effects) {
   $image_effects_definition_called = &drupal_static(__FUNCTION__, 0);
   $image_effects_definition_called++;
 }
+
+/**
+ * Implements hook_image_style_presave().
+ *
+ * Used to save test third party settings in the image style entity.
+ */
+function image_module_test_image_style_presave(ImageStyleInterface $style) {
+  $style->setThirdPartySetting('image_module_test', 'foo', 'bar');
+}