diff --git a/src/classes/entities/class-tainacan-field.php b/src/classes/entities/class-tainacan-field.php
index 5650489cf..9aef33a14 100644
--- a/src/classes/entities/class-tainacan-field.php
+++ b/src/classes/entities/class-tainacan-field.php
@@ -370,7 +370,7 @@ class Field extends Entity {
         $fto = $this->get_field_type_object();
 
         if (is_object($fto)) {
-            $is_valid = $fto->validate_options($this->get_field_type_options());
+            $is_valid = $fto->validate_options($this);
         }
         
         if (true === $is_valid)
diff --git a/src/classes/field-types/category/class-tainacan-category.php b/src/classes/field-types/category/class-tainacan-category.php
index b32e818e0..9be693fa0 100644
--- a/src/classes/field-types/category/class-tainacan-category.php
+++ b/src/classes/field-types/category/class-tainacan-category.php
@@ -60,18 +60,49 @@ class Category extends Field_Type {
                         
                     <?php endforeach; ?>
                 </select>
+            </td>
+			<td>
+                <label><?php echo __('Allow creation of new terms','tainacan'); ?></label><br/>
+                <small><?php echo __('If checked, users may create new terms for this category, otherwise they can only selected from existing terms.','tainacan'); ?></small>
+            </td>
+            <td>
+                <input type="checkbox" name="allow_new_terms" <?php checked(true, $this->get_option('allow_new_terms')); ?> >
+				<label>Allow</label>
             </td>
         </tr>
         <?php
     }
 	
-	public function validate_options(Array $options) {
+	public function validate_options(\Tainacan\Entities\Field $field) {
+		
+		if ( !in_array($field->get_status(), apply_filters('tainacan-status-require-validation', ['publish','future','private'])) )
+            return true;
+		
+		if (empty($this->get_option('taxonomy_id')))
+			return ['taxonomy_id' => __('Please select a category', 'tainacan')];
+		
+		global $Tainacan_Fields;
+		
+		$category_fields = $Tainacan_Fields->fetch([
+			'collection_id' => $field->get_collection_id(),
+			'field_type' => 'Tainacan\\Field_Types\\Category'
+		], 'OBJECT');
+		
+		$category_fields = array_map(function ($field) {
+			$fto = $field->get_field_type_object();
+			return $fto->get_option('taxonomy_id');
+		}, $category_fields);
+		
+		if (in_array($this->get_option('taxonomy_id'), $category_fields)) {
+			return ['taxonomy_id' => __('You can not have 2 Category Fields using the same category in a collection', 'tainacan')];
+		}
+		
 		return true;
-		// TODO validate required and unique taxonomy
+		
 	}
 	
 	/**
-     * Validate item based on field type categores options
+     * Validate item based on field type categories options
      *
      * @param  TainacanEntitiesItem_Metadata_Entity $item_metadata
      * @return bool Valid or not
@@ -88,6 +119,10 @@ class Category extends Field_Type {
         
         if (false === $this->get_option('allow_new_terms')) {
 			$terms = $item_metadata->get_value();
+			
+			if (false === $terms)
+				return true;
+			
 			if (!is_array($terms))
 				$terms = array($terms);
 			
diff --git a/src/classes/field-types/field-type/class-tainacan-field-type.php b/src/classes/field-types/field-type/class-tainacan-field-type.php
index 7de8bda39..b3eede15c 100644
--- a/src/classes/field-types/field-type/class-tainacan-field-type.php
+++ b/src/classes/field-types/field-type/class-tainacan-field-type.php
@@ -145,10 +145,10 @@ abstract class Field_Type  {
      *
      * This method should be declared by each field type sub classes
      * 
-     * @param  Array  $options Options to be saved as field_type_optins
+     * @param  \Tainacan\Entities\Field  $field The field object that is beeing validated
      * @return true|Array True if optinos are valid. If invalid, returns an array where keys are the field keys and values are error messages.
      */
-    public function validate_options(Array $options) {
+    public function validate_options(\Tainacan\Entities\Field $field) {
         return true;
     }
 
diff --git a/src/classes/field-types/relationship/class-tainacan-relationship.php b/src/classes/field-types/relationship/class-tainacan-relationship.php
index 0675275c0..ef2a0982d 100644
--- a/src/classes/field-types/relationship/class-tainacan-relationship.php
+++ b/src/classes/field-types/relationship/class-tainacan-relationship.php
@@ -98,9 +98,9 @@ class Relationship extends Field_Type {
         <?php
     }
     
-    public function validate_options(Array $options) {
+    public function validate_options(\Tainacan\Entities\Field $field) {
         // TODO: This is just a sample validation to test validation workflow for field types. Must redo it
-        if (isset($options['collection_id']) && !is_numeric($options['collection_id'])) {
+        if (!empty($this->get_option('collection_id')) && !is_numeric($this->get_option('collection_id'))) {
             return [
                 'collection_id' => 'Collection ID invalid'
             ];
diff --git a/src/classes/repositories/class-tainacan-fields.php b/src/classes/repositories/class-tainacan-fields.php
index fd74daaec..430433aa8 100644
--- a/src/classes/repositories/class-tainacan-fields.php
+++ b/src/classes/repositories/class-tainacan-fields.php
@@ -286,7 +286,9 @@ class Fields extends Repository {
                 'posts_per_page' => -1,
                 'post_status'    => 'publish'
             ], $args);
-
+			
+			$args = $this->parse_fetch_args($args);
+			
             $args['post_type'] = Entities\Field::get_post_type();
 
             $wp_query = new \WP_Query($args);
diff --git a/tests/test-category-field-types.php b/tests/test-category-field-types.php
index d8a7332d3..19e83cb87 100644
--- a/tests/test-category-field-types.php
+++ b/tests/test-category-field-types.php
@@ -40,10 +40,11 @@ class CategoryFieldTypes extends TAINACAN_UnitTestCase {
         $field = $this->tainacan_entity_factory->create_entity(
         	'field',
 	        array(
-	        	'name' => 'metadado',
-		        'description' => 'title',
+	        	'name' => 'meta',
+		        'description' => 'description',
 		        'collection' => $collection,
 		        'field_type' => 'Tainacan\Field_Types\Category',
+				'status'	 => 'publish',
 				'field_type_options' => [
 					'taxonomy_id' => $tax->get_db_identifier(),
 					'allow_new_terms' => false
@@ -55,10 +56,11 @@ class CategoryFieldTypes extends TAINACAN_UnitTestCase {
         $field2 = $this->tainacan_entity_factory->create_entity(
         	'field',
 	        array(
-	        	'name' => 'metadado_desc',
+	        	'name' => 'meta2',
 		        'description' => 'description',
 		        'collection' => $collection,
-		        'field_type' => 'Tainacan\Field_Types\Category'
+		        'field_type' => 'Tainacan\Field_Types\Category',
+				'status'	 => 'draft',
 	        ),
 	        true
         );
@@ -111,6 +113,17 @@ class CategoryFieldTypes extends TAINACAN_UnitTestCase {
 		$check_item_metadata = new \Tainacan\Entities\Item_Metadata_Entity($checkItem, $field);
 
 		$this->assertEquals('WP_Term', get_class($check_item_metadata->get_value()));
+		
+		// test 2 fields with same category
+		$field2->set_field_type_options([
+			'taxonomy_id' => $tax->get_db_identifier(),
+		]);
+		$field2->set_status('publish');
+		
+		$this->assertFalse($field2->validate(), 'Category Field should not validate when using a category in use by another field in the same collection');
+		$errors = $field2->get_errors();
+		$this->assertInternalType('array', $errors);
+		$this->assertArrayHasKey('taxonomy_id', $errors[0]);
     }
     
 }
\ No newline at end of file