diff --git a/app/Http/Controllers/Api/CustomFieldsController.php b/app/Http/Controllers/Api/CustomFieldsController.php
index 43100f8fa..fb0493046 100644
--- a/app/Http/Controllers/Api/CustomFieldsController.php
+++ b/app/Http/Controllers/Api/CustomFieldsController.php
@@ -2,11 +2,14 @@
 
 namespace App\Http\Controllers\Api;
 
+use App\Helpers\Helper;
 use App\Http\Controllers\Controller;
 use App\Http\Transformers\CustomFieldsTransformer;
 use App\Models\CustomField;
 use App\Models\CustomFieldset;
 use Illuminate\Http\Request;
+use Validator;
+use Illuminate\Validation\Rule;
 
 class CustomFieldsController extends Controller
 {
@@ -27,6 +30,81 @@ class CustomFieldsController extends Controller
         $total = count($fields);
         return (new CustomFieldsTransformer)->transformCustomFields($fields, $total);
     }
+
+    /**
+    * Shows the given field
+    * @author [V. Cordes] [<volker@fdatek.de>]
+    * @param int $id
+    * @since [v4.1.10]
+    * @return View
+    */
+    public function show($id)
+    {
+      $this->authorize('show', CustomField::class);
+        if ($field = CustomField::find($id)) {
+            return (new CustomFieldsTransformer)->transformCustomField($field);
+        }
+
+        return response()->json(Helper::formatStandardApiResponse('error', null, trans('admin/custom_fields/message.field.invalid')), 200);
+    }
+
+     /**
+     * Update the specified field
+     *
+     * @author [V. Cordes] [<volker@fdatek.de>]
+     * @since [v4.1.10]
+     * @param  \Illuminate\Http\Request  $request
+     * @param  int  $id
+     * @return \Illuminate\Http\Response
+     */
+    public function update(Request $request, $id)
+    {
+        $this->authorize('edit', CustomField::class);
+        $field = CustomField::findOrFail($id);
+        $data = $request->all();
+
+        $validator = Validator::make($data, $field->validationRules());
+        if ($validator->fails()) {
+            return response()->json(Helper::formatStandardApiResponse('error', null, $validator->errors()));
+        }
+
+        $field->fill($data);
+
+        if ($field->save()) {
+            return response()->json(Helper::formatStandardApiResponse('success', $field, trans('admin/custom_fields/message.field.update.success')));
+        }
+
+        return response()->json(Helper::formatStandardApiResponse('error', null, $field->getErrors()));
+    }
+
+
+    /**
+     * Store a newly created field.
+     *
+     * @author [V. Cordes] [<volker@fdatek.de>]
+     * @since [v4.1.10]
+     * @param  \Illuminate\Http\Request  $request
+     * @return \Illuminate\Http\Response
+     */
+    public function store(Request $request)
+    {
+        $this->authorize('create', CustomField::class);
+        $field = new CustomField;
+
+        $data = $request->all();
+        $validator = Validator::make($data, $field->validationRules());
+        if ($validator->fails()) {
+            return response()->json(Helper::formatStandardApiResponse('error', null, $validator->errors()));
+        }
+        $field->fill($data);
+
+        if ($field->save()) {
+            return response()->json(Helper::formatStandardApiResponse('success', $field, trans('admin/custom_fields/message.field.create.success')));
+        }
+        return response()->json(Helper::formatStandardApiResponse('error', null, $field->getErrors()));
+
+    }
+
     public function postReorder(Request $request, $id)
     {
         $fieldset = CustomFieldset::find($id);
@@ -62,7 +140,7 @@ class CustomFieldsController extends Controller
         if ($field->fieldset->count() >0) {
             return response()->json(Helper::formatStandardApiResponse('error', null, 'Field is in use.'));
         }
-        
+
         $field->delete();
         return response()->json(Helper::formatStandardApiResponse('success', null,  trans('admin/custom_fields/message.field.delete.success')));
 
diff --git a/app/Http/Transformers/CustomFieldsTransformer.php b/app/Http/Transformers/CustomFieldsTransformer.php
index 4d41ce232..6e6a50a7e 100644
--- a/app/Http/Transformers/CustomFieldsTransformer.php
+++ b/app/Http/Transformers/CustomFieldsTransformer.php
@@ -22,6 +22,7 @@ class CustomFieldsTransformer
     {
 
         $array = [
+            'id' => $field->id,
             'name' => e($field->name),
             'db_column_name' => e($field->db_column_name()),
             'format'   =>  e($field->format),
diff --git a/app/Models/CustomField.php b/app/Models/CustomField.php
index 5906fed92..c744705f1 100644
--- a/app/Models/CustomField.php
+++ b/app/Models/CustomField.php
@@ -8,6 +8,7 @@ use App\Http\Traits\UniqueUndeletedTrait;
 use ForceUTF8\Encoding;
 use EasySlugger\Utf8Slugger;
 use Patchwork\Utf8;
+use Illuminate\Validation\Rule;
 
 class CustomField extends Model
 {
@@ -29,8 +30,18 @@ class CustomField extends Model
         "BOOLEAN" => "boolean",
     ];
 
-    public $rules = [
-        "name" => "required|unique:custom_fields"
+    /**
+     * The attributes that are mass assignable.
+     *
+     * @var array
+     */
+    protected $fillable = [
+        'name',
+        'element',
+        'format',
+        'field_values',
+        'field_encrypted',
+        'help_text'
     ];
 
     // This is confusing, since it's actually the custom fields table that
@@ -160,7 +171,7 @@ class CustomField extends Model
     public function getFormatAttribute($value)
     {
         foreach (self::$PredefinedFormats as $name => $pattern) {
-            if ($pattern === $value) {
+            if ($pattern === $value || $name === $value) {
                 return $name;
             }
         }
@@ -248,4 +259,26 @@ class CustomField extends Model
 
         return substr($long_slug, 0, 50) . '_' . $id;
     }
+
+    /**
+    * Get validation rules for custom fields to use with Validator
+    * @author [V. Cordes] [<volker@fdatek.de>]
+    * @param int $id
+    * @since [v4.1.10]
+    * @return Array
+    */
+    public function validationRules()
+    {
+        return [
+            "name" => "required|unique:custom_fields",
+            "element" => [
+                "required",
+                Rule::in(['text', 'listbox'])
+            ],
+            'format' => [
+                Rule::in(array_merge(array_keys(CustomField::$PredefinedFormats), CustomField::$PredefinedFormats))
+            ],
+            'field_encrypted' => "nullable|boolean"
+        ];
+    }
 }
diff --git a/routes/api.php b/routes/api.php
index c70014265..36646956c 100644
--- a/routes/api.php
+++ b/routes/api.php
@@ -200,6 +200,18 @@ Route::group(['prefix' => 'v1','namespace' => 'Api'], function () {
 
     /*--- Fields API ---*/
 
+    Route::resource('fields', 'CustomFieldsController', [
+        'names' => [
+            'index' => 'api.customfields.index',
+            'show' => 'api.customfields.show',
+            'store' => 'api.customfields.store',
+            'update' => 'api.customfields.update',
+            'destroy' => 'api.customfields.destroy'
+        ],
+        'except' => [ 'create', 'edit' ],
+        'parameters' => [ 'field' => 'field_id' ]
+    ]);
+
     Route::group(['prefix' => 'fields'], function () {
         Route::post('fieldsets/{id}/order',
             [
@@ -207,13 +219,6 @@ Route::group(['prefix' => 'v1','namespace' => 'Api'], function () {
                 'uses' => 'CustomFieldsController@postReorder'
             ]
         );
-
-        Route::get('/',
-            [
-                'as' => 'api.customfields.index',
-                'uses' => 'CustomFieldsController@index'
-            ]
-        );
     }); // Fields group