diff --git a/extra_field.api.php b/extra_field.api.php
index cff967e..08b3c34 100644
--- a/extra_field.api.php
+++ b/extra_field.api.php
@@ -41,6 +41,18 @@ function hook_extra_field_display_info_alter(array &$info) {
   $info['all_nodes']['bundles'][] = 'taxonomy_term.*';
 }
 
+/**
+ * Perform alterations on Extra Field Form Displays.
+ *
+ * @param array $info
+ *   An array of information on existing Extra Field Form Displays, as collected
+ *   by the annotation discovery mechanism.
+ */
+function hook_extra_field_form_info_alter(array &$info) {
+  // Let a plugin also be used for all taxonomy terms.
+  $info['all_nodes']['bundles'][] = 'taxonomy_term.*';
+}
+
 /**
  * @} End of "addtogroup hooks".
  */
diff --git a/extra_field.module b/extra_field.module
index d0140d7..7fcd1b5 100644
--- a/extra_field.module
+++ b/extra_field.module
@@ -5,15 +5,22 @@
  * Hook implementations for Extra Field module.
  */
 
+use Drupal\Core\Entity\ContentEntityFormInterface;
 use Drupal\Core\Entity\Display\EntityViewDisplayInterface;
 use Drupal\Core\Entity\EntityInterface;
+use Drupal\Core\Form\ConfirmFormInterface;
+use Drupal\Core\Form\FormStateInterface;
 
 /**
  * Implements hook_entity_extra_field_info().
  */
 function extra_field_entity_extra_field_info() {
+  $info_form = \Drupal::service('plugin.manager.extra_field_form_display')
+    ->fieldInfo();
+  $info_display = \Drupal::service('plugin.manager.extra_field_display')
+    ->fieldInfo();
 
-  return \Drupal::service('plugin.manager.extra_field_display')->fieldInfo();
+  return array_merge_recursive($info_form, $info_display);
 }
 
 /**
@@ -24,3 +31,16 @@ function extra_field_entity_view(array &$build, EntityInterface $entity, EntityV
   /** @var \Drupal\Core\Entity\ContentEntityInterface $entity */
   \Drupal::service('plugin.manager.extra_field_display')->entityView($build, $entity, $display, $view_mode);
 }
+
+/**
+ * Implements hook_form_alter().
+ */
+function extra_field_form_alter(array &$form, FormStateInterface $form_state) {
+  $form_object = $form_state->getFormObject();
+  if ($form_object instanceof ContentEntityFormInterface
+    && !$form_object instanceof ConfirmFormInterface
+  ) {
+    $display = $form_object->getFormDisplay($form_state);
+    \Drupal::service('plugin.manager.extra_field_form_display')->entityFormAlter($display, $form, $form_state);
+  }
+}
diff --git a/extra_field.services.yml b/extra_field.services.yml
index bb9951f..809597a 100644
--- a/extra_field.services.yml
+++ b/extra_field.services.yml
@@ -2,3 +2,7 @@ services:
   plugin.manager.extra_field_display:
     class: Drupal\extra_field\Plugin\ExtraFieldDisplayManager
     arguments: ['@container.namespaces', '@cache.discovery', '@module_handler', '@entity_type.manager']
+
+  plugin.manager.extra_field_form:
+    class: Drupal\extra_field\Plugin\ExtraFieldFormManager
+    arguments: ['@container.namespaces', '@cache.discovery', '@module_handler', '@entity_type.manager']
diff --git a/modules/extra_field_example/src/Plugin/ExtraField/Form/ExampleAllNodes.php b/modules/extra_field_example/src/Plugin/ExtraField/Form/ExampleAllNodes.php
new file mode 100644
index 0000000..ef8d479
--- /dev/null
+++ b/modules/extra_field_example/src/Plugin/ExtraField/Form/ExampleAllNodes.php
@@ -0,0 +1,53 @@
+<?php
+
+namespace Drupal\extra_field_example\Plugin\ExtraField\Form;
+
+use Drupal\Core\Form\FormStateInterface;
+use Drupal\extra_field\Plugin\ExtraFieldFormBase;
+
+/**
+ * Example Extra field form Display.
+ *
+ * @ExtraFieldForm(
+ *   id = "all_nodes_example",
+ *   label = @Translation("For all nodes"),
+ *   bundles = {
+ *     "node.*"
+ *   },
+ *   weight = -30,
+ *   visible = true
+ * )
+ */
+class ExampleAllNodes extends ExtraFieldFormBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function view(array $form, FormStateInterface $form_state) {
+    // Here you can use elements of different types.
+    $element = [
+      '#type' => 'submit',
+      '#value' => $this->t('Custom submit'),
+      '#submit' => [
+        '::submitForm',
+        [self::class, 'customSubmit'],
+      ],
+    ];
+
+    return $element;
+  }
+
+  /**
+   * Handle custom submit.
+   *
+   * @param array $form
+   *   The form array.
+   * @param \Drupal\Core\Form\FormStateInterface $form_state
+   *   The form state object.
+   */
+  public static function customSubmit(array $form, FormStateInterface $form_state) {
+    // TODO Don't use deprecated functions (or example without dependency)
+    drupal_set_message('Custom submit was triggered.');
+  }
+
+}
diff --git a/modules/extra_field_example/src/Plugin/ExtraField/Form/ExampleFormAllNodes.php b/modules/extra_field_example/src/Plugin/ExtraField/Form/ExampleFormAllNodes.php
new file mode 100644
index 0000000..fefd004
--- /dev/null
+++ b/modules/extra_field_example/src/Plugin/ExtraField/Form/ExampleFormAllNodes.php
@@ -0,0 +1,52 @@
+<?php
+
+namespace Drupal\extra_field_example\Plugin\ExtraField\Form;
+
+use Drupal\Core\Form\FormStateInterface;
+use Drupal\extra_field\Plugin\ExtraFieldFormBase;
+
+/**
+ * Example Extra field form Display.
+ *
+ * @ExtraFieldForm(
+ *   id = "all_nodes_example",
+ *   label = @Translation("For all nodes custom form element"),
+ *   bundles = {
+ *     "node.*"
+ *   },
+ *   weight = -30,
+ *   visible = true
+ * )
+ */
+class ExampleFormAllNodes extends ExtraFieldFormBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function formView(array $form, FormStateInterface $form_state) {
+    // Here you can use elements of different types.
+    $element = [
+      '#type' => 'submit',
+      '#value' => $this->t('Custom submit'),
+      '#submit' => [
+        '::submitForm',
+        [self::class, 'customSubmit'],
+      ],
+    ];
+
+    return $element;
+  }
+
+  /**
+   * Custom submit.
+   *
+   * @param array $form
+   *   The form array.
+   * @param \Drupal\Core\Form\FormStateInterface $form_state
+   *   The form state object.
+   */
+  public static function customSubmit(array $form, FormStateInterface $form_state) {
+    drupal_set_message('Custom submit was triggered.');
+  }
+
+}
diff --git a/src/Annotation/ExtraFieldForm.php b/src/Annotation/ExtraFieldForm.php
new file mode 100644
index 0000000..f150cbc
--- /dev/null
+++ b/src/Annotation/ExtraFieldForm.php
@@ -0,0 +1,56 @@
+<?php
+
+namespace Drupal\extra_field\Annotation;
+
+use Drupal\Component\Annotation\Plugin;
+
+/**
+ * Defines a ExtraFieldForm item annotation object.
+ *
+ * @see \Drupal\extra_field\Plugin\ExtraFieldFormManager
+ *
+ * @Annotation
+ */
+class ExtraFieldForm extends Plugin {
+
+  /**
+   * The plugin ID.
+   *
+   * @var string
+   */
+  public $id;
+
+  /**
+   * The label of the plugin.
+   *
+   * @var \Drupal\Core\Annotation\Translation
+   *
+   * @ingroup plugin_translatable
+   */
+  public $label;
+
+  /**
+   * The entity + bundle combination(s) the plugin supports.
+   *
+   * Format: [entity].[bundle] for specific entity-bundle combinations or
+   * [entity].* for all bundles of the entity.
+   *
+   * @var string[]
+   */
+  public $bundles = [];
+
+  /**
+   * The default weight of the field.
+   *
+   * @var int
+   */
+  public $weight = 0;
+
+  /**
+   * Whether the field is visible by default.
+   *
+   * @var bool
+   */
+  public $visible = FALSE;
+
+}
diff --git a/src/Plugin/ExtraFieldDisplayManager.php b/src/Plugin/ExtraFieldDisplayManager.php
index c8920ab..8fe3933 100644
--- a/src/Plugin/ExtraFieldDisplayManager.php
+++ b/src/Plugin/ExtraFieldDisplayManager.php
@@ -109,6 +109,8 @@ class ExtraFieldDisplayManager extends DefaultPluginManager implements ExtraFiel
   /**
    * Checks if the plugin bundle definition matches the entity bundle key.
    *
+   * TODO: Move this method to ExtraFieldManagerTrait.
+   *
    * @param string[] $pluginBundles
    *   Defines which entity-bundle pair the plugin can be used for.
    *   Format: [entity type].[bundle] or [entity type].* .
@@ -142,6 +144,7 @@ class ExtraFieldDisplayManager extends DefaultPluginManager implements ExtraFiel
    * Returns entity-bundle combinations this plugin supports.
    *
    * If a wildcard bundle is set, all bundles of the entity will be included.
+   * TODO: Move this method to ExtraFieldManagerTrait.
    *
    * @param string[] $entityBundleKeys
    *   Array of entity-bundle strings that define the bundles for which the
@@ -181,6 +184,8 @@ class ExtraFieldDisplayManager extends DefaultPluginManager implements ExtraFiel
   /**
    * Returns the bundles that are defined for an entity type.
    *
+   * TODO: Move this method to ExtraFieldManagerTrait.
+   *
    * @param string $entityType
    *   The entity type to get the bundles for.
    *
@@ -212,6 +217,8 @@ class ExtraFieldDisplayManager extends DefaultPluginManager implements ExtraFiel
   /**
    * Build the field name string.
    *
+   * TODO: Move this method to ExtraFieldManagerTrait.
+   *
    * @param string $pluginId
    *   The machine name of the Extra Field plugin.
    *
@@ -226,6 +233,8 @@ class ExtraFieldDisplayManager extends DefaultPluginManager implements ExtraFiel
   /**
    * Creates a key string with entity type and bundle.
    *
+   * TODO: Move this method to ExtraFieldManagerTrait.
+   *
    * @param string $entityType
    *   The entity type.
    * @param string $bundle
diff --git a/src/Plugin/ExtraFieldFormBase.php b/src/Plugin/ExtraFieldFormBase.php
new file mode 100644
index 0000000..fddd1b3
--- /dev/null
+++ b/src/Plugin/ExtraFieldFormBase.php
@@ -0,0 +1,60 @@
+<?php
+
+namespace Drupal\extra_field\Plugin;
+
+use Drupal\Component\Plugin\PluginBase;
+use Drupal\Core\Entity\Display\EntityFormDisplayInterface;
+use Drupal\Core\StringTranslation\StringTranslationTrait;
+
+/**
+ * Base class for Extra field form display plugins.
+ */
+abstract class ExtraFieldFormBase extends PluginBase implements ExtraFieldFormInterface {
+
+  use StringTranslationTrait;
+
+  /**
+   * The form mode.
+   *
+   * @var string
+   */
+  protected $formMode;
+
+  /**
+   * The entity form display.
+   *
+   * Contains the form display options configured for the entity components.
+   *
+   * @var \Drupal\Core\Entity\Display\EntityFormDisplayInterface
+   */
+  protected $entityFormDisplay;
+
+  /**
+   * {@inheritdoc}
+   */
+  public function setEntityFormDisplay(EntityFormDisplayInterface $display) {
+    $this->entityFormDisplay = $display;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getEntityFormDisplay() {
+    return $this->entityFormDisplay;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function setFormMode($form_mode) {
+    $this->formMode = $form_mode;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function getFormMode() {
+    return $this->formMode;
+  }
+
+}
diff --git a/src/Plugin/ExtraFieldFormInterface.php b/src/Plugin/ExtraFieldFormInterface.php
new file mode 100644
index 0000000..78e78e8
--- /dev/null
+++ b/src/Plugin/ExtraFieldFormInterface.php
@@ -0,0 +1,60 @@
+<?php
+
+namespace Drupal\extra_field\Plugin;
+
+use Drupal\Component\Plugin\PluginInspectionInterface;
+use Drupal\Core\Entity\Display\EntityFormDisplayInterface;
+use Drupal\Core\Form\FormStateInterface;
+
+/**
+ * Defines an interface for Extra Field Form plugins.
+ */
+interface ExtraFieldFormInterface extends PluginInspectionInterface {
+
+  /**
+   * Builds a renderable array for the field.
+   *
+   * @param array $form
+   *   The entity form array.
+   * @param \Drupal\Core\Form\FormStateInterface $form_state
+   *   The form state object.
+   *
+   * @return array
+   *   Renderable array.
+   */
+  public function view(array $form, FormStateInterface $form_state);
+
+  /**
+   * Stores the entity form display.
+   *
+   * @param \Drupal\Core\Entity\Display\EntityFormDisplayInterface $display
+   *   The entity form display holding the display options configured for the
+   *   entity components.
+   */
+  public function setEntityFormDisplay(EntityFormDisplayInterface $display);
+
+  /**
+   * Returns the entity form display object of the field's host entity.
+   *
+   * @return \Drupal\Core\Entity\Display\EntityFormDisplayInterface
+   *   The entity view display object.
+   */
+  public function getEntityFormDisplay();
+
+  /**
+   * Stores the entity form mode.
+   *
+   * @param string $form_mode
+   *   The form mode the entity is rendered in.
+   */
+  public function setFormMode($form_mode);
+
+  /**
+   * Returns the entity form mode of the field's host entity.
+   *
+   * @return string
+   *   The form mode the field is being rendered in.
+   */
+  public function getFormMode();
+
+}
diff --git a/src/Plugin/ExtraFieldFormManager.php b/src/Plugin/ExtraFieldFormManager.php
new file mode 100644
index 0000000..0c99fbf
--- /dev/null
+++ b/src/Plugin/ExtraFieldFormManager.php
@@ -0,0 +1,253 @@
+<?php
+
+namespace Drupal\extra_field\Plugin;
+
+use Drupal\Core\Entity\Display\EntityFormDisplayInterface;
+use Drupal\Core\Entity\EntityTypeManagerInterface;
+use Drupal\Core\Form\FormStateInterface;
+use Drupal\Core\Plugin\DefaultPluginManager;
+use Drupal\Core\Cache\CacheBackendInterface;
+use Drupal\Core\Extension\ModuleHandlerInterface;
+
+/**
+ * Manages Extra Field form plugins.
+ *
+ * @package Drupal\extra_field\Plugin
+ */
+class ExtraFieldFormManager extends DefaultPluginManager implements ExtraFieldFormManagerInterface {
+
+  /**
+   * Caches bundles per entity type.
+   *
+   * @var array
+   */
+  protected $entityBundles;
+
+  /**
+   * The entity type manager.
+   *
+   * @var \Drupal\Core\Entity\EntityTypeManagerInterface
+   */
+  protected $entityTypeManager;
+
+  /**
+   * Constructor for ExtraFieldFormManager object.
+   *
+   * @param \Traversable $namespaces
+   *   An object that implements \Traversable which contains the root paths
+   *   keyed by the corresponding namespace to look for plugin implementations.
+   * @param \Drupal\Core\Cache\CacheBackendInterface $cache_backend
+   *   Cache backend instance to use.
+   * @param \Drupal\Core\Extension\ModuleHandlerInterface $module_handler
+   *   The module handler to invoke the alter hook with.
+   * @param \Drupal\Core\Entity\EntityTypeManagerInterface $entity_type_manager
+   *   The entity type manager.
+   */
+  public function __construct(\Traversable $namespaces, CacheBackendInterface $cache_backend, ModuleHandlerInterface $module_handler, EntityTypeManagerInterface $entity_type_manager) {
+
+    parent::__construct('Plugin/ExtraField/Form', $namespaces, $module_handler, 'Drupal\extra_field\Plugin\ExtraFieldFormInterface', 'Drupal\extra_field\Annotation\ExtraFieldForm');
+
+    $this->alterInfo('extra_field_form_info');
+    $this->setCacheBackend($cache_backend, 'extra_field_form_plugins');
+    $this->entityTypeManager = $entity_type_manager;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function fieldInfo() {
+    $info = [];
+    $definitions = $this->getDefinitions();
+
+    foreach ($definitions as $key => $definition) {
+      $entityBundles = $this->supportedEntityBundles($definition['bundles']);
+
+      foreach ($entityBundles as $entityBundle) {
+        $entity_type = $entityBundle['entity'];
+        $bundle = $entityBundle['bundle'];
+        $fieldName = $this->fieldName($key);
+        $info[$entity_type][$bundle]['form'][$fieldName] = [
+          'label' => $definition['label'],
+          'weight' => $definition['weight'],
+          'visible' => $definition['visible'],
+        ];
+      }
+    }
+
+    return $info;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function entityFormAlter(EntityFormDisplayInterface $display, array &$form, FormStateInterface $formState) {
+    $entityType = $display->getTargetEntityTypeId();
+    $entityBundleKey = $this->entityBundleKey($entityType, $display->get('bundle'));
+    foreach ($this->getDefinitions() as $definition) {
+      if ($this->matchEntityBundleKey($definition['bundles'], $entityBundleKey)) {
+
+        $factory = $this->getFactory();
+        $pluginId = $definition['id'];
+        if ($extraField = $display->getComponent($this->fieldName($pluginId))) {
+
+          /** @var ExtraFieldFormInterface $plugin */
+          $plugin = $factory->createInstance($pluginId);
+          $fieldName = $this->fieldName($pluginId);
+          $plugin->setEntityFormDisplay($display);
+          $plugin->setFormMode($display->get('mode'));
+          $element = $plugin->view($form, $formState);
+          if (!empty($element)) {
+            $form[$fieldName] = [
+              '#weight' => $extraField['weight'],
+              '#type' => 'container',
+              'widget' => $element,
+            ];
+          }
+        }
+      }
+    }
+  }
+
+  /**
+   * Checks if the plugin bundle definition matches the entity bundle key.
+   *
+   * TODO: Move this method to ExtraFieldManagerTrait.
+   *
+   * @param string[] $pluginBundles
+   *   Defines which entity-bundle pair the plugin can be used for.
+   *   Format: [entity type].[bundle] or [entity type].* .
+   * @param string $entityBundleKey
+   *   The entity-bundle string of a content entity.
+   *   Format: [entity type].[bundle] .
+   *
+   * @return bool
+   *   True of the plugin bundle definition matches the entity bundle key.
+   */
+  protected function matchEntityBundleKey(array $pluginBundles, $entityBundleKey) {
+
+    $match = FALSE;
+    foreach ($pluginBundles as $pluginBundle) {
+      if (strpos($pluginBundle, '.*')) {
+        $match = explode('.', $pluginBundle)[0] == explode('.', $entityBundleKey)[0];
+      }
+      else {
+        $match = $pluginBundle == $entityBundleKey;
+      }
+
+      if ($match) {
+        break;
+      }
+    }
+
+    return $match;
+  }
+
+  /**
+   * Returns entity-bundle combinations this plugin supports.
+   *
+   * If a wildcard bundle is set, all bundles of the entity will be included.
+   * TODO: Move this method to ExtraFieldManagerTrait.
+   *
+   * @param string[] $entityBundleKeys
+   *   Array of entity-bundle strings that define the bundles for which the
+   *   plugin can be used. Format: [entity].[bundle]
+   *   '*' can be used as bundle wildcard.
+   *
+   * @return array
+   *   Array of entity and bundle names. Keyed by the [entity].[bundle] key.
+   */
+  protected function supportedEntityBundles(array $entityBundleKeys) {
+
+    $result = [];
+    foreach ($entityBundleKeys as $entityBundleKey) {
+      if (strpos($entityBundleKey, '.')) {
+        list($entityType, $bundle) = explode('.', $entityBundleKey);
+        if ($bundle == '*') {
+          foreach ($this->allEntityBundles($entityType) as $bundle) {
+            $key = $this->entityBundleKey($entityType, $bundle);
+            $result[$key] = [
+              'entity' => $entityType,
+              'bundle' => $bundle,
+            ];
+          }
+        }
+        else {
+          $result[$entityBundleKey] = [
+            'entity' => $entityType,
+            'bundle' => $bundle,
+          ];
+        }
+      }
+    }
+
+    return $result;
+  }
+
+  /**
+   * Returns the bundles that are defined for an entity type.
+   *
+   * TODO: Move this method to ExtraFieldManagerTrait.
+   *
+   * @param string $entityType
+   *   The entity type to get the bundles for.
+   *
+   * @return string[]
+   *   Array of bundle names.
+   */
+  protected function allEntityBundles($entityType) {
+
+    if (!isset($this->entityBundles[$entityType])) {
+      $bundleType = $this->entityTypeManager
+        ->getDefinition($entityType)
+        ->getBundleEntityType();
+
+      if ($bundleType) {
+        $bundles = $this->entityTypeManager
+          ->getStorage($bundleType)
+          ->getQuery()
+          ->execute();
+      }
+      else {
+        $bundles = [$entityType => $entityType];
+      }
+      $this->entityBundles[$entityType] = $bundles;
+    }
+
+    return $this->entityBundles[$entityType];
+  }
+
+  /**
+   * Build the field name string.
+   *
+   * TODO: Move this method to ExtraFieldManagerTrait.
+   *
+   * @param string $pluginId
+   *   The machine name of the Extra Field plugin.
+   *
+   * @return string
+   *   Field name.
+   */
+  protected function fieldName($pluginId) {
+
+    return 'extra_field_' . $pluginId;
+  }
+
+  /**
+   * Creates a key string with entity type and bundle.
+   *
+   * TODO: Move this method to ExtraFieldManagerTrait.
+   *
+   * @param string $entityType
+   *   The entity type.
+   * @param string $bundle
+   *   The bundle.
+   *
+   * @return string
+   *   Formatted string.
+   */
+  protected function entityBundleKey($entityType, $bundle) {
+
+    return "$entityType.$bundle";
+  }
+
+}
diff --git a/src/Plugin/ExtraFieldFormManagerInterface.php b/src/Plugin/ExtraFieldFormManagerInterface.php
new file mode 100644
index 0000000..ee3ba55
--- /dev/null
+++ b/src/Plugin/ExtraFieldFormManagerInterface.php
@@ -0,0 +1,37 @@
+<?php
+
+namespace Drupal\extra_field\Plugin;
+
+use Drupal\Core\Entity\Display\EntityFormDisplayInterface;
+use Drupal\Core\Form\FormStateInterface;
+
+/**
+ * Provides the Extra field form display plugin manager.
+ */
+interface ExtraFieldFormManagerInterface {
+
+  /**
+   * Exposes the ExtraFieldForm plugins to hook_entity_extra_field_info.
+   *
+   * @return array
+   *   The array structure is identical to that of the return value of
+   *   \Drupal\Core\Entity\EntityFieldManagerInterface::getExtraFields().
+   *
+   * @see hook_entity_extra_field_info()
+   */
+  public function fieldInfo();
+
+  /**
+   * Appends the renderable data from ExtraFieldForm plugins to hook_form_alter.
+   *
+   * @param \Drupal\Core\Entity\Display\EntityFormDisplayInterface $display
+   *   The entity form display holding the display options configured for the
+   *   entity components.
+   * @param array $form
+   *   The entity form array.
+   * @param \Drupal\Core\Form\FormStateInterface $formState
+   *   The form state object.
+   */
+  public function entityFormAlter(EntityFormDisplayInterface $display, array &$form, FormStateInterface $formState);
+
+}