diff --git a/core/modules/content_moderation/content_moderation.services.yml b/core/modules/content_moderation/content_moderation.services.yml
index 904bc0dc335ae51100a6be8ecff01af4a7345230..256095a03af0878b7a4b3792941b9128da2eb056 100644
--- a/core/modules/content_moderation/content_moderation.services.yml
+++ b/core/modules/content_moderation/content_moderation.services.yml
@@ -19,4 +19,9 @@ services:
     class: Drupal\content_moderation\RevisionTracker
     arguments: ['@database']
     tags:
-     - { name: backend_overridable }
+      - { name: backend_overridable }
+  content_moderation.config_import_subscriber:
+    class: Drupal\content_moderation\EventSubscriber\ConfigImportSubscriber
+    arguments: ['@config.manager', '@entity_type.manager']
+    tags:
+      - { name: event_subscriber }
diff --git a/core/modules/content_moderation/src/EventSubscriber/ConfigImportSubscriber.php b/core/modules/content_moderation/src/EventSubscriber/ConfigImportSubscriber.php
new file mode 100644
index 0000000000000000000000000000000000000000..bb7d6802830a9c65ed2d2f6aaf313f63580eb2e7
--- /dev/null
+++ b/core/modules/content_moderation/src/EventSubscriber/ConfigImportSubscriber.php
@@ -0,0 +1,96 @@
+<?php
+
+namespace Drupal\content_moderation\EventSubscriber;
+
+use Drupal\Core\Config\ConfigImporterEvent;
+use Drupal\Core\Config\ConfigImportValidateEventSubscriberBase;
+use Drupal\Core\Config\ConfigManagerInterface;
+use Drupal\Core\Config\Entity\ConfigEntityStorage;
+use Drupal\Core\Entity\EntityTypeManagerInterface;
+
+/**
+ * Check moderation states are not being used before updating workflow config.
+ */
+class ConfigImportSubscriber extends ConfigImportValidateEventSubscriberBase {
+
+  /**
+   * The config manager.
+   *
+   * @var \Drupal\Core\Config\ConfigManagerInterface
+   */
+  protected $configManager;
+
+  /**
+   * The entity type manager.
+   *
+   * @var \Drupal\Core\Entity\EntityTypeManagerInterface
+   */
+  protected $entityTypeManager;
+
+  /**
+   * Constructs the event subscriber.
+   *
+   * @param \Drupal\Core\Config\ConfigManagerInterface $config_manager
+   *   The config manager
+   * @param \Drupal\Core\Entity\EntityTypeManagerInterface $entity_type_manager
+   *   The entity type manager.
+   */
+  public function __construct(ConfigManagerInterface $config_manager, EntityTypeManagerInterface $entity_type_manager) {
+    $this->configManager = $config_manager;
+    $this->entityTypeManager = $entity_type_manager;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function onConfigImporterValidate(ConfigImporterEvent $event) {
+    foreach (['update', 'delete'] as $op) {
+      $unprocessed_configurations = $event->getConfigImporter()->getUnprocessedConfiguration($op);
+      foreach ($unprocessed_configurations as $unprocessed_configuration) {
+        if ($workflow = $this->getWorkflow($unprocessed_configuration)) {
+          if ($op === 'update') {
+            $original_workflow_config = $event->getConfigImporter()
+              ->getStorageComparer()
+              ->getSourceStorage()
+              ->read($unprocessed_configuration);
+            $workflow_config = $event->getConfigImporter()
+              ->getStorageComparer()
+              ->getTargetStorage()
+              ->read($unprocessed_configuration);
+            $diff = array_diff_key($workflow_config['type_settings']['states'], $original_workflow_config['type_settings']['states']);
+            foreach (array_keys($diff) as $state_id) {
+              $state = $workflow->getState($state_id);
+              if ($workflow->getTypePlugin()->workflowStateHasData($workflow, $state)) {
+                $event->getConfigImporter()->logError($this->t('The moderation state @state_label is being used, but is not in the source storage.', ['@state_label' => $state->label()]));
+              }
+            }
+          }
+          if ($op === 'delete') {
+            if ($workflow->getTypePlugin()->workflowHasData($workflow)) {
+              $event->getConfigImporter()->logError($this->t('The workflow @workflow_label is being used, and cannot be deleted.', ['@workflow_label' => $workflow->label()]));
+            }
+          }
+        }
+      }
+    }
+  }
+
+  /**
+   * Get the workflow entity object from the configuration name.
+   *
+   * @param string $config_name
+   *   The configuration object name.
+   *
+   * @return \Drupal\Core\Entity\EntityInterface|null
+   *   An entity object. NULL if no matching entity is found.
+   */
+  protected function getWorkflow($config_name) {
+    $entity_type_id = $this->configManager->getEntityTypeIdByName($config_name);
+    /** @var \Drupal\Core\Config\Entity\ConfigEntityTypeInterface $entity_type */
+    $entity_type = $this->entityTypeManager->getDefinition($entity_type_id);
+    $entity_id = ConfigEntityStorage::getIDFromConfigName($config_name, $entity_type->getConfigPrefix());
+    /** @var \Drupal\workflows\WorkflowInterface $workflow */
+    return $this->entityTypeManager->getStorage($entity_type_id)->load($entity_id);
+  }
+
+}
diff --git a/core/modules/content_moderation/src/Plugin/WorkflowType/ContentModeration.php b/core/modules/content_moderation/src/Plugin/WorkflowType/ContentModeration.php
index c45803ab83e5175fd3e106f3386f6203707437a3..f4bbef553d86e436fad1eb429420504047003da2 100644
--- a/core/modules/content_moderation/src/Plugin/WorkflowType/ContentModeration.php
+++ b/core/modules/content_moderation/src/Plugin/WorkflowType/ContentModeration.php
@@ -114,6 +114,35 @@ public function decorateState(StateInterface $state) {
     return $state;
   }
 
+  /**
+   * {@inheritdoc}
+   */
+  public function workflowHasData(WorkflowInterface $workflow) {
+    return (bool) $this->entityTypeManager
+      ->getStorage('content_moderation_state')
+      ->getQuery()
+      ->condition('workflow', $workflow->id())
+      ->count()
+      ->accessCheck(FALSE)
+      ->range(0, 1)
+      ->execute();
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function workflowStateHasData(WorkflowInterface $workflow, StateInterface $state) {
+    return (bool) $this->entityTypeManager
+      ->getStorage('content_moderation_state')
+      ->getQuery()
+      ->condition('workflow', $workflow->id())
+      ->condition('moderation_state', $state->id())
+      ->count()
+      ->accessCheck(FALSE)
+      ->range(0, 1)
+      ->execute();
+  }
+
   /**
    * {@inheritdoc}
    */
diff --git a/core/modules/content_moderation/tests/src/Functional/ModerationFormTest.php b/core/modules/content_moderation/tests/src/Functional/ModerationFormTest.php
index 7aab0d46c3d22e8cf651dc562341ef9b82e04b25..b6fe577fb48329a97d6b32d6ad7e19e9c1ad1883 100644
--- a/core/modules/content_moderation/tests/src/Functional/ModerationFormTest.php
+++ b/core/modules/content_moderation/tests/src/Functional/ModerationFormTest.php
@@ -451,4 +451,53 @@ public function testContentTranslationNodeForm() {
     $this->drupalPostForm(NULL, [], t('Save and Create New Draft (this translation)'));
   }
 
+  /**
+   * Tests that workflows and states can not be deleted if they are in use.
+   *
+   * @covers \Drupal\content_moderation\Plugin\WorkflowType\ContentModeration::workflowHasData
+   * @covers \Drupal\content_moderation\Plugin\WorkflowType\ContentModeration::workflowStateHasData
+   */
+  public function testWorkflowInUse() {
+    $user = $this->createUser([
+      'administer workflows',
+      'create moderated_content content',
+      'edit own moderated_content content',
+      'use editorial transition create_new_draft',
+      'use editorial transition publish',
+      'use editorial transition archive'
+    ]);
+    $this->drupalLogin($user);
+    $paths = [
+      'archived_state' => 'admin/config/workflow/workflows/manage/editorial/state/archived/delete',
+      'editorial_workflow' => 'admin/config/workflow/workflows/manage/editorial/delete',
+    ];
+    foreach ($paths as $path) {
+      $this->drupalGet($path);
+      $this->assertSession()->buttonExists('Delete');
+    }
+    // Create new moderated content in draft.
+    $this->drupalPostForm('node/add/moderated_content', [
+      'title[0][value]' => 'Some moderated content',
+      'body[0][value]' => 'First version of the content.',
+    ], 'Save and Create New Draft');
+
+    // The archived state is not used yet, so can still be deleted.
+    $this->drupalGet($paths['archived_state']);
+    $this->assertSession()->buttonExists('Delete');
+
+    // The workflow is being used, so can't be deleted.
+    $this->drupalGet($paths['editorial_workflow']);
+    $this->assertSession()->buttonNotExists('Delete');
+
+    $node = $this->drupalGetNodeByTitle('Some moderated content');
+    $this->drupalPostForm('node/' . $node->id() . '/edit', [], 'Save and Publish');
+    $this->drupalPostForm('node/' . $node->id() . '/edit', [], 'Save and Archive');
+
+    // Now the archived state is being used so it can not be deleted either.
+    foreach ($paths as $path) {
+      $this->drupalGet($path);
+      $this->assertSession()->buttonNotExists('Delete');
+    }
+  }
+
 }
diff --git a/core/modules/content_moderation/tests/src/Kernel/ContentModerationWorkflowConfigTest.php b/core/modules/content_moderation/tests/src/Kernel/ContentModerationWorkflowConfigTest.php
new file mode 100644
index 0000000000000000000000000000000000000000..90ecfcf2dd14f216af152957ca217e5e8be805c4
--- /dev/null
+++ b/core/modules/content_moderation/tests/src/Kernel/ContentModerationWorkflowConfigTest.php
@@ -0,0 +1,132 @@
+<?php
+
+namespace Drupal\Tests\content_moderation\Kernel;
+
+use Drupal\Core\Config\ConfigImporterException;
+use Drupal\KernelTests\KernelTestBase;
+use Drupal\node\Entity\Node;
+use Drupal\node\Entity\NodeType;
+use Drupal\workflows\Entity\Workflow;
+
+/**
+ * Tests how Content Moderation handles workflow config changes.
+ *
+ * @group content_moderation
+ */
+class ContentModerationWorkflowConfigTest extends KernelTestBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public static $modules = [
+    'node',
+    'content_moderation',
+    'user',
+    'system',
+    'text',
+    'workflows',
+  ];
+
+  /**
+   * @var \Drupal\Core\Entity\EntityTypeManager
+   */
+  protected $entityTypeManager;
+
+  /**
+   * @var \Drupal\Core\Config\ConfigFactoryInterface
+   */
+  protected $configFactory;
+
+  /**
+   * @var \Drupal\workflows\Entity\Workflow
+   */
+  protected $workflow;
+
+  /**
+   * @var \Drupal\Core\Config\Entity\ConfigEntityStorage
+   */
+  protected $workflowStorage;
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function setUp() {
+    parent::setUp();
+
+    $this->installSchema('node', 'node_access');
+    $this->installEntitySchema('node');
+    $this->installEntitySchema('user');
+    $this->installEntitySchema('content_moderation_state');
+    $this->installConfig('content_moderation');
+
+    NodeType::create([
+      'type' => 'example',
+    ])->save();
+
+    $workflow = Workflow::load('editorial');
+    $workflow->getTypePlugin()
+      ->addState('test1', 'Test one')
+      ->addState('test2', 'Test two')
+      ->addState('test3', 'Test three')
+      ->addEntityTypeAndBundle('node', 'example');
+    $workflow->save();
+    $this->workflow = $workflow;
+
+    $this->copyConfig($this->container->get('config.storage'), $this->container->get('config.storage.sync'));
+  }
+
+  /**
+   * Test deleting a state via config import.
+   */
+  public function testDeletingStateViaConfiguration() {
+    $config_data = $this->config('workflows.workflow.editorial')->get();
+    unset($config_data['type_settings']['states']['test1']);
+    \Drupal::service('config.storage.sync')->write('workflows.workflow.editorial', $config_data);
+
+    // There are no Nodes with the moderation state test1, so this should run
+    // with no errors.
+    $this->configImporter()->reset()->import();
+
+    $node = Node::create([
+      'type' => 'example',
+      'title' => 'Test title',
+      'moderation_state' => 'test2',
+    ]);
+    $node->save();
+
+    $config_data = $this->config('workflows.workflow.editorial')->get();
+    unset($config_data['type_settings']['states']['test2']);
+    unset($config_data['type_settings']['states']['test3']);
+    \Drupal::service('config.storage.sync')->write('workflows.workflow.editorial', $config_data);
+
+    // Now there is a Node with the moderation state test2, this will fail.
+    try {
+      $this->configImporter()->reset()->import();
+      $this->fail('ConfigImporterException not thrown, invalid import was not stopped due to deleted state.');
+    }
+    catch (ConfigImporterException $e) {
+      $this->assertEqual($e->getMessage(), 'There were errors validating the config synchronization.');
+      $error_log = $this->configImporter->getErrors();
+      $expected = ['The moderation state Test two is being used, but is not in the source storage.'];
+      $this->assertEqual($expected, $error_log);
+    }
+
+    \Drupal::service('config.storage.sync')->delete('workflows.workflow.editorial');
+
+    // An error should be thrown when trying to delete an in use workflow.
+    try {
+      $this->configImporter()->reset()->import();
+      $this->fail('ConfigImporterException not thrown, invalid import was not stopped due to deleted workflow.');
+    }
+    catch (ConfigImporterException $e) {
+      $this->assertEqual($e->getMessage(), 'There were errors validating the config synchronization.');
+      $error_log = $this->configImporter->getErrors();
+      $expected = [
+        'The moderation state Test two is being used, but is not in the source storage.',
+        'The workflow Editorial workflow is being used, and cannot be deleted.',
+      ];
+      $this->assertEqual($expected, $error_log);
+    }
+  }
+
+}
diff --git a/core/modules/workflows/src/Form/WorkflowDeleteForm.php b/core/modules/workflows/src/Form/WorkflowDeleteForm.php
index b9b833132b73ffb8c79b9a6eed722eabc336be97..e122f4054346bb6f102aeec95d46baed30c7fc77 100644
--- a/core/modules/workflows/src/Form/WorkflowDeleteForm.php
+++ b/core/modules/workflows/src/Form/WorkflowDeleteForm.php
@@ -11,6 +11,19 @@
  */
 class WorkflowDeleteForm extends EntityConfirmFormBase {
 
+  /**
+   * {@inheritdoc}
+   */
+  public function buildForm(array $form, FormStateInterface $form_state) {
+    if ($this->entity->getTypePlugin()->workflowHasData($this->entity)) {
+      $form['#title'] = $this->getQuestion();
+      $form['description'] = ['#markup' => $this->t('This workflow is in use. You cannot remove this workflow until you have removed all content using it.')];
+      return $form;
+    }
+
+    return parent::buildForm($form, $form_state);
+  }
+
   /**
    * {@inheritdoc}
    */
diff --git a/core/modules/workflows/src/Form/WorkflowStateDeleteForm.php b/core/modules/workflows/src/Form/WorkflowStateDeleteForm.php
index c60045ca23a57487f38cea856e428fc0c46c010e..d2c30d7435c55cc236fc6d1656c25e6af4def307 100644
--- a/core/modules/workflows/src/Form/WorkflowStateDeleteForm.php
+++ b/core/modules/workflows/src/Form/WorkflowStateDeleteForm.php
@@ -75,6 +75,13 @@ public function buildForm(array $form, FormStateInterface $form_state, WorkflowI
     }
     $this->workflow = $workflow;
     $this->stateId = $workflow_state;
+
+    if ($this->workflow->getTypePlugin()->workflowStateHasData($this->workflow, $this->workflow->getState($this->stateId))) {
+      $form['#title'] = $this->getQuestion();
+      $form['description'] = ['#markup' => $this->t('This workflow state is in use. You cannot remove this workflow state until you have removed all content using it.')];
+      return $form;
+    }
+
     return parent::buildForm($form, $form_state);
   }
 
diff --git a/core/modules/workflows/src/Plugin/WorkflowTypeBase.php b/core/modules/workflows/src/Plugin/WorkflowTypeBase.php
index 0c4a34f427c2cdbfaed4fc30e62023a34add7f7a..efdfe7e10ddc652b927d68e6356e47c32d82f69a 100644
--- a/core/modules/workflows/src/Plugin/WorkflowTypeBase.php
+++ b/core/modules/workflows/src/Plugin/WorkflowTypeBase.php
@@ -61,6 +61,20 @@ public function checkWorkflowAccess(WorkflowInterface $entity, $operation, Accou
     return AccessResult::neutral();
   }
 
+  /**
+   * {@inheritdoc}
+   */
+  public function workflowHasData(WorkflowInterface $workflow) {
+    return FALSE;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function workflowStateHasData(WorkflowInterface $workflow, StateInterface $state) {
+    return FALSE;
+  }
+
   /**
    * {@inheritdoc}
    */
diff --git a/core/modules/workflows/src/WorkflowTypeInterface.php b/core/modules/workflows/src/WorkflowTypeInterface.php
index d84d1a7ad4fdd6117851fbdf4cbf61ea3aee94d4..6ff8832d78d672677bc2d6746de74426df65718a 100644
--- a/core/modules/workflows/src/WorkflowTypeInterface.php
+++ b/core/modules/workflows/src/WorkflowTypeInterface.php
@@ -56,6 +56,38 @@ public function label();
    */
   public function checkWorkflowAccess(WorkflowInterface $entity, $operation, AccountInterface $account);
 
+  /**
+   * Determines if the workflow is being has data associated with it.
+   *
+   * @internal
+   *   Marked as internal until it's validated this should form part of the
+   *   public API in https://www.drupal.org/node/2897148.
+   *
+   * @param \Drupal\workflows\WorkflowInterface $workflow
+   *   The workflow to check.
+   *
+   * @return bool
+   *   TRUE if the workflow is being used, FALSE if not.
+   */
+  public function workflowHasData(WorkflowInterface $workflow);
+
+  /**
+   * Determines if the workflow state has data associated with it.
+   *
+   * @internal
+   *   Marked as internal until it's validated this should form part of the
+   *   public API in https://www.drupal.org/node/2897148.
+   *
+   * @param \Drupal\workflows\WorkflowInterface $workflow
+   *   The workflow to check.
+   * @param \Drupal\workflows\StateInterface $state
+   *   The workflow state to check.
+   *
+   * @return bool
+   *   TRUE if the workflow state is being used, FALSE if not.
+   */
+  public function workflowStateHasData(WorkflowInterface $workflow, StateInterface $state);
+
   /**
    * Decorates states so the WorkflowType can add additional information.
    *