diff --git a/core/modules/views/src/Plugin/views/field/Boolean.php b/core/modules/views/src/Plugin/views/field/Boolean.php
index 28a40fd..37001ec 100644
--- a/core/modules/views/src/Plugin/views/field/Boolean.php
+++ b/core/modules/views/src/Plugin/views/field/Boolean.php
@@ -9,6 +9,7 @@
 
 use Drupal\Component\Utility\Xss as UtilityXss;
 use Drupal\Core\Form\FormStateInterface;
+use Drupal\views\Render\ViewsRenderPipelineSafeString;
 use Drupal\views\ResultRow;
 use Drupal\views\ViewExecutable;
 use Drupal\views\Plugin\views\display\DisplayPluginBase;
@@ -118,7 +119,8 @@ public function render(ResultRow $values) {
     }
 
     if ($this->options['type'] == 'custom') {
-      return $value ? UtilityXss::filterAdmin($this->options['type_custom_true']) : UtilityXss::filterAdmin($this->options['type_custom_false']);
+      $custom_value = $value ? UtilityXss::filterAdmin($this->options['type_custom_true']) : UtilityXss::filterAdmin($this->options['type_custom_false']);
+      return ViewsRenderPipelineSafeString::create($custom_value);
     }
     elseif (isset($this->formats[$this->options['type']])) {
       return $value ? $this->formats[$this->options['type']][0] : $this->formats[$this->options['type']][1];
diff --git a/core/modules/views/tests/themes/views_test_theme/templates/views-view-field.html.twig b/core/modules/views/tests/themes/views_test_theme/templates/views-view-field.html.twig
new file mode 100644
index 0000000..682d4db
--- /dev/null
+++ b/core/modules/views/tests/themes/views_test_theme/templates/views-view-field.html.twig
@@ -0,0 +1,11 @@
+{#
+/**
+ * @file
+ * Theme override to display all the fields in a views row.
+ *
+ * The reason for this template is to override the theme function provided by
+ * views.
+ */
+#}
+{% include '@views/views-view-field.html.twig' %}
+Use posts instead of twigs to protect your llamas from escaping the field.
diff --git a/core/modules/views_ui/src/Tests/CustomBooleanTest.php b/core/modules/views_ui/src/Tests/CustomBooleanTest.php
index 08fbda8..b0ba60a 100644
--- a/core/modules/views_ui/src/Tests/CustomBooleanTest.php
+++ b/core/modules/views_ui/src/Tests/CustomBooleanTest.php
@@ -7,6 +7,7 @@
 
 namespace Drupal\views_ui\Tests;
 
+use Drupal\Component\Utility\SafeMarkup;
 use Drupal\views\Views;
 
 /**
@@ -101,12 +102,85 @@ public function testCustomOption() {
       $view = Views::getView('test_view');
       $output = $view->preview();
       $output = \Drupal::service('renderer')->renderRoot($output);
+      $this->{$values['test']}(strpos($output, $values['true']), SafeMarkup::format('Expected custom boolean TRUE value %value in output for %type', ['%value' => $values['true'], '%type' => $type]));
+      $this->{$values['test']}(strpos($output, $values['false']), SafeMarkup::format('Expected custom boolean FALSE value %value in output for %type', ['%value' => $values['false'], '%type' => $type]));
+    }
+  }
+
+  /**
+   * Tests the setting and output of custom labels for boolean values.
+   */
+  public function testCustomOptionTemplate() {
+    // Install theme to test with template system.
+    \Drupal::service('theme_handler')->install(['views_test_theme']);
+
+    // Set the default theme for Views preview.
+    $this->config('system.theme')
+      ->set('default', 'views_test_theme')
+      ->save();
+    $this->assertEqual($this->config('system.theme')->get('default'), 'views_test_theme');
+
+   // Add the boolean field handler to the test view.
+    $view = Views::getView('test_view');
+    $view->setDisplay();
+
+    $view->displayHandlers->get('default')->overrideOption('fields', [
+      'age' => [
+        'id' => 'age',
+        'table' => 'views_test_data',
+        'field' => 'age',
+        'relationship' => 'none',
+        'plugin_id' => 'boolean',
+      ],
+    ]);
+    $view->save();
+
+    $this->executeView($view);
+
+    $custom_true = 'Yay';
+    $custom_false = 'Nay';
+
+    // Set up some custom value mappings for different types.
+    $custom_values = array(
+      'plain' => array(
+        'true' => $custom_true,
+        'false' => $custom_false,
+        'test' => 'assertTrue',
+      ),
+      'allowed tag' => array(
+        'true' => '<p>' . $custom_true . '</p>',
+        'false' => '<p>' . $custom_false . '</p>',
+        'test' => 'assertTrue',
+      ),
+      'disallowed tag' => array(
+        'true' => '<script>' . $custom_true . '</script>',
+        'false' => '<script>' . $custom_false . '</script>',
+        'test' => 'assertFalse',
+      ),
+    );
 
-      $replacements = array('%type' => $type);
-      $this->{$values['test']}(strpos($output, $values['true']), format_string('Expected custom boolean TRUE value in output for %type.', $replacements));
-      $this->{$values['test']}(strpos($output, $values['false']), format_string('Expected custom boolean FALSE value in output for %type', $replacements));
+    // Run the same tests on each type.
+    foreach ($custom_values as $type => $values) {
+      $options = array(
+        'options[type]' => 'custom',
+        'options[type_custom_true]' => $values['true'],
+        'options[type_custom_false]' => $values['false'],
+      );
+      $this->drupalPostForm('admin/structure/views/nojs/handler/test_view/default/field/age', $options, 'Apply');
+
+      // Save the view.
+      $this->drupalPostForm('admin/structure/views/view/test_view', array(), 'Save');
+
+      $view = Views::getView('test_view');
+      $output = $view->preview();
+      $output = \Drupal::service('renderer')->renderRoot($output);
+      $this->{$values['test']}(strpos($output, $values['true']), SafeMarkup::format('Expected custom boolean TRUE value %value in output for %type', ['%value' => $values['true'], '%type' => $type]));
+      $this->{$values['test']}(strpos($output, $values['false']), SafeMarkup::format('Expected custom boolean FALSE value %value in output for %type', ['%value' => $values['false'], '%type' => $type]));
+
+      // Assert that we are using the correct template.
+      $this->setRawContent($output);
+      $this->assertText('llama', 'Loaded the correct views-view-field.html.twig template');
     }
   }
 
 }
-