diff --git a/app/Config/SettingsRepository.php b/app/Config/SettingsRepository.php
index 1070d85..c87b748 100644
--- a/app/Config/SettingsRepository.php
+++ b/app/Config/SettingsRepository.php
@@ -88,6 +88,25 @@ public function defaultHideInNav()
 		return false;
 	}
 
+
+	/**
+	 * Number of available page groups before selection is required
+	 * @return int
+	 */
+	public function maxNonSelectedPageGroups()
+	{
+		$value = 3;
+		$option = get_option('nestedpages_ui', false);
+		if ( is_array($option) )
+			if ( array_key_exists('max_nonselected_pagegroups', $option) ) {
+				if ( is_numeric($option['max_nonselected_pagegroups']) ) {
+					if ( $option['max_nonselected_pagegroups'] >= -1 ) $value = $option['max_nonselected_pagegroups'];
+				}
+			}
+		if ( $value < -1 ) $value = -1;
+		return $value;
+	}
+
 	/**
 	* Are menus completely disabled?
 	* @return boolean
@@ -262,4 +281,5 @@ public function sortViewEnabled()
 		endif;
 		return $roles;
 	}
-}
\ No newline at end of file
+
+}
diff --git a/app/Entities/AdminMenu/BlockEditorLink.php b/app/Entities/AdminMenu/BlockEditorLink.php
index 9816d13..340ffb8 100644
--- a/app/Entities/AdminMenu/BlockEditorLink.php
+++ b/app/Entities/AdminMenu/BlockEditorLink.php
@@ -55,6 +55,8 @@ private function fullPageEditorLink($type)
 		if ( !$user_can_view ) return;
 		$link = ( $type->name == 'page' ) ? 'admin.php?page=nestedpages' : 'admin.php?page=' . $this->post_type_repo->getMenuSlug($type);
 		$url = admin_url($link);
+		$pagegroup = $this->post_repo->getPageGroup(get_post()->ID);
+		if ( $pagegroup !== false ) $url .= '&np_page_group=' . $pagegroup;
 		echo '<script>jQuery(window).on("load", function(){ var headerLink = jQuery(".edit-post-header .edit-post-fullscreen-mode-close"); jQuery(headerLink).attr("href", "' . $url . '"); });</script>';
 	}
-}
\ No newline at end of file
+}
diff --git a/app/Entities/Listing/Listing.php b/app/Entities/Listing/Listing.php
index 395ecc0..a833117 100644
--- a/app/Entities/Listing/Listing.php
+++ b/app/Entities/Listing/Listing.php
@@ -127,6 +127,18 @@ class Listing
 	*/
 	private $status_preference;
 
+	/**
+	 * Current page group
+	 * @var ?int
+	 */
+	private $page_group_id;
+
+	/**
+	 * Available page groups
+	 * @var array
+	 */
+	private $page_groups;
+
 	/**
 	* Enabled Custom Fields
 	*/
@@ -150,6 +162,8 @@ public function __construct($post_type)
 		$this->setPostTypeSettings();
 		$this->setStandardFields();
 		$this->setStatusPreference();
+		$this->loadPageGroups();
+		$this->setPageGroup();
 	}
 
 	/**
@@ -359,15 +373,42 @@ private function publishedChildrenCount($post)
 		return $publish_count;
 	}
 
+	/**
+	 * Load all the available page groups
+	 */
+	private function loadPageGroups() {
+		$this->page_groups = $this->listing_query->getPosts($this->post_type, $this->h_taxonomies, $this->f_taxonomies, null, true);
+	}
+
+	/**
+	 * Set the page group from the HTTP request
+	 */
+	private function setPageGroup() {
+		$this->page_group_id = null;
+		if ( array_key_exists( 'np_page_group', $_REQUEST ) ) {
+			if ( is_numeric( $_REQUEST['np_page_group'] ) )
+				$this->page_group_id = $_REQUEST['np_page_group'];
+		}
+		$this->all_posts = [];
+	}
+
 	/**
 	* Loop through all the pages and create the nested / sortable list
 	* Called in listing.php view
 	*/
-	private function getPosts()
+	private function printPostsList()
 	{
-		$this->all_posts = $this->listing_query->getPosts($this->post_type, $this->h_taxonomies, $this->f_taxonomies);
-		$this->listPostLevel();
-		return;
+		$max_nonselected_pagegroups = $this->settings->maxNonSelectedPageGroups();
+		if ( $max_nonselected_pagegroups == -1 )
+			$list_due_to_pagegroups = true;
+		else if ( $max_nonselected_pagegroups == 0 )
+			$list_due_to_pagegroups = false;
+		else
+			$list_due_to_pagegroups = count($this->page_groups) <= $max_nonselected_pagegroups;
+		if ( $list_due_to_pagegroups || $this->page_group_id !== null || $this->listing_repo->isSearch() ) {
+			$this->all_posts = $this->listing_query->getPosts($this->post_type, $this->h_taxonomies, $this->f_taxonomies, $this->page_group_id, false);
+			$this->listPostLevel();
+		}
 	}
 
 	/**
diff --git a/app/Entities/Listing/ListingQuery.php b/app/Entities/Listing/ListingQuery.php
index 7ec9f9a..fe64e05 100644
--- a/app/Entities/Listing/ListingQuery.php
+++ b/app/Entities/Listing/ListingQuery.php
@@ -5,6 +5,7 @@
 use NestedPages\Entities\PostType\PostTypeRepository;
 use NestedPages\Config\SettingsRepository;
 use NestedPages\Entities\PluginIntegration\IntegrationFactory;
+use NestedPages\Entities\Post\PostRepository;
 
 /**
 * Performs the query for the page listing and formats into a multidemensional array
@@ -73,7 +74,7 @@ private function setOrder()
 	/**
 	* Get the Posts
 	*/
-	public function getPosts($post_type, $h_taxonomies = [], $f_taxonomies = [])
+	public function getPosts($post_type, $h_taxonomies = [], $f_taxonomies = [], $page_group_id = null, $only_page_groups = false)
 	{
 		$this->post_type = $post_type;
 
@@ -91,7 +92,8 @@ public function getPosts($post_type, $h_taxonomies = [], $f_taxonomies = [])
 			$post_type = [$post_type->name];
 		}
 
-		$statuses = ['publish', 'pending', 'draft', 'private', 'future', 'trash'];
+		$statuses = ['publish', 'pending', 'draft', 'private', 'future'];
+		if ( !$only_page_groups ) $statuses[] = 'trash';
 		$post_type_settings = $this->post_type_repo->getSinglePostType($post_type[0]);
 		if ( isset($post_type_settings->custom_statuses) ) $statuses = array_merge($statuses, $post_type_settings->custom_statuses);
 		
@@ -101,23 +103,33 @@ public function getPosts($post_type, $h_taxonomies = [], $f_taxonomies = [])
 			'author' => $this->sort_options->author,
 			'orderby' => $this->sort_options->orderby,
 			'post_status' => apply_filters('nestedpages_listing_statuses', $statuses, $this->post_type),
-			'order' => $this->sort_options->order
+			'order' => $this->sort_options->order,
+			'suppress_filters' => false,
+			'nested_pages_page_group' => $page_group_id, 
 		];
 		
 		if ( $this->listing_repo->isSearch() ) $query_args = $this->searchParams($query_args);
 		if ( $this->listing_repo->isFiltered() ) $query_args = $this->filterParams($query_args);
 		if ( $this->sort_options->tax_query ) $query_args['tax_query'] = $this->sort_options->tax_query;
+		if ( $page_group_id !== null )
+			$query_args['post__in'] = PostRepository::getPostsOfPageGroup(
+			  $page_group_id,
+			  [ 'post_type' =>
+			    [
+			      'include' => ['page']
+			    ],
+			  ]
+			);
+		if ( $only_page_groups ) $query_args['post_parent'] = 0;
 		
 		$query_args = apply_filters('nestedpages_page_listing', $query_args, $this->post_type);
 		
-		add_filter( 'posts_clauses', [$this, 'queryFilter']);
+		add_filter( 'posts_clauses', [$this, 'queryFilter'] );
 		$all_posts = new \WP_Query($query_args);
-		remove_filter( 'posts_clauses', [$this, 'queryFilter']);
-		
-		if ( $all_posts->have_posts() ) :
-			return $all_posts->posts;
-		endif; wp_reset_postdata();
-		return null;
+		remove_filter( 'posts_clauses', [$this, 'queryFilter'] );
+
+		if ( ! $all_posts->have_posts() ) wp_reset_postdata();
+		return $all_posts->posts;
 	}
 
 	/**
@@ -166,7 +178,12 @@ private function setTaxonomyFilters()
 	public function queryFilter($pieces)
 	{
 		global $wpdb;
-		
+
+		// Restrict fields to avoid loading the post contents
+		$pieces['fields'] = 'ID, post_author, post_date, post_date_gmt, post_title, post_status,'
+			. ' post_name, post_modified, post_modified_gmt, post_parent, guid, menu_order,'
+			. ' post_type, post_mime_type, comment_count';
+
 		// Add Hierarchical Categories
 		$c = 0;
 		foreach($this->h_taxonomies as $tax){
@@ -209,11 +226,12 @@ public function queryFilter($pieces)
 							LEFT JOIN `$wpdb->term_taxonomy` AS $tt ON $tt.term_taxonomy_id = $tr.term_taxonomy_id AND $tt.taxonomy = '$name'
 							LEFT JOIN `$wpdb->terms` AS $t ON $t.term_id = $tt.term_id";
 				endif ;
-				$pieces['fields'] .= ",GROUP_CONCAT(DISTINCT $t.term_id SEPARATOR ',') AS '$name'";
+				$pieces['fields'] .= ", GROUP_CONCAT(DISTINCT $t.term_id SEPARATOR ',') AS '$name'";
 				$c++;
 		}
 
 		$pieces['groupby'] = "$wpdb->posts.ID"; 
 		return $pieces;
 	}
-}
\ No newline at end of file
+
+}
diff --git a/app/Entities/PluginIntegration/WPML.php b/app/Entities/PluginIntegration/WPML.php
index 323b4b2..ef016e6 100644
--- a/app/Entities/PluginIntegration/WPML.php
+++ b/app/Entities/PluginIntegration/WPML.php
@@ -344,4 +344,15 @@ public function getPostTypeCountByLanguage($post_type, $language = null)
 		$query = $wpdb->prepare("SELECT COUNT(*) FROM {$wpdb->prefix}posts AS p LEFT JOIN {$wpdb->prefix}icl_translations AS trans ON p.ID = trans.element_id WHERE post_type = %s AND p.post_status = 'publish' AND trans.language_code = %s", $post_type, $language);
 		return $wpdb->get_var($query);
 	}
+
+	/**
+	 * Get language of given post ID
+	 * @param $post_id int - the post ID
+	 * @return string or null - language code
+	 */
+	public function getPostLanguage($post_id)
+	{
+		$langauge_details = apply_filters('wpml_post_language_details', null, $post_id);
+		return $langauge_details['language_code'] ?? null;
+	}
 }
diff --git a/app/Entities/Post/PostRepository.php b/app/Entities/Post/PostRepository.php
index 19e0fa7..9631984 100644
--- a/app/Entities/Post/PostRepository.php
+++ b/app/Entities/Post/PostRepository.php
@@ -222,4 +222,71 @@ public function getChildren($parent_id, $post_type, $posts = [])
 		}
 		return $posts;
 	}
-}
\ No newline at end of file
+
+	/**
+	 * Return posts of a page group (recursion function)
+	 */
+	private static function getChildPosts_recurse(int $toplevel_id, array &$pages, string &$sqlWhere) {
+		global $wpdb;
+		$sqlQuery = "select id from {$wpdb->posts} where post_parent = {$toplevel_id} $sqlWhere";
+		$rows_sub_ids = $wpdb->get_results($sqlQuery, ARRAY_A);
+		foreach ( $rows_sub_ids as &$row_sub_id ) {
+			$sub_id = $row_sub_id['id'];
+			$pages[] = $sub_id;
+			self::getChildPosts_recurse($sub_id, $pages, $sqlWhere);
+		}
+		unset($row_sub_id);
+	}
+
+	/**
+	 * Get child posts of a post
+	 */
+	public static function getChildPosts(int $toplevel_id, array $args = []) {
+		$sqlWhere = '';
+		foreach ( ['post_type', 'post_status'] as $field ) {
+			if ( array_key_exists($field, $args) ) {
+				foreach ( ['include', 'exclude'] as $rule ) {
+					if ( array_key_exists( $rule, $args[$field] ) ) {
+						$sqlWhere .= \NestedPages\Helpers::getSQLWhere($rule == 'include', $field, (array)$args[$field][$rule]);
+					}
+				}
+			}
+		}
+		$page_ids = [ $toplevel_id ];
+		self::getChildPosts_recurse($toplevel_id, $page_ids, $sqlWhere);
+		return $page_ids;
+	}
+
+	/**
+	 * Get posts of a page group.
+	 * By default, it returns all related posts.
+	 */
+	public static function getPostsOfPageGroup(int $post_id, ?array $postTypes = null) {
+		$page_ids = self::getChildPosts( self::getPageGroup($post_id), $postTypes );
+		return $page_ids;
+	}
+
+	/**
+	 * Return page group of the given post
+	 */
+	public static function getPageGroup(int $post_id) {
+		global $wpdb;
+		$pagegroup = false;
+		$has_error = false;
+		$p_id = $post_id;
+		do {
+			$rows = $wpdb->get_results("select id, post_parent from {$wpdb->posts} where post_type = 'page' and id = " . $p_id, ARRAY_A);
+			if ( count( $rows ) == 1 ) {
+				if ( $rows[0]['post_parent'] ) {
+					$p_id = $rows[0]['post_parent'];
+				} else {
+					$pagegroup = $rows[0]['id'];
+				}
+			} else
+				$has_error = true;
+		} while ( ! $has_error && $pagegroup === false );
+		return $has_error ? false : $pagegroup;
+	}
+
+
+}
diff --git a/app/Form/Listeners/ListingSort.php b/app/Form/Listeners/ListingSort.php
index 77c985f..50e8b3d 100644
--- a/app/Form/Listeners/ListingSort.php
+++ b/app/Form/Listeners/ListingSort.php
@@ -39,6 +39,8 @@ private function setURL()
 		$this->setOrder();
 		$this->setAuthor();
 		$this->setTaxonomies();
+		$this->setPageGroup();
+		$this->setLanguage();
 	}
 
 	/**
@@ -81,4 +83,22 @@ private function setTaxonomies()
 			endif;
 		endforeach;
 	}
-}
\ No newline at end of file
+
+		/**
+	* Set page group
+	*/
+	private function setPageGroup()
+	{
+		if ( isset($_POST['np_page_group']) && $_POST['np_page_group'] !== '' ) $this->url .= '&np_page_group=' . sanitize_text_field($_POST['np_page_group']);
+	}
+
+	/**
+	 * Set language
+	 */
+	private function setLanguage()
+	{
+		if ( isset($_POST['lang']) ) $this->url .= '&lang=' . sanitize_text_field($_POST['lang']);
+	}
+
+
+}
diff --git a/app/Helpers.php b/app/Helpers.php
index 2f7d9d8..8b1f4be 100644
--- a/app/Helpers.php
+++ b/app/Helpers.php
@@ -41,4 +41,22 @@ public static function defaultPagesLink($type = 'page')
 		$link = esc_url( admin_url('edit.php?post_type=' . $type ) );
 		return $link;
 	}
-}
\ No newline at end of file
+
+	/**
+	 * Return a part of an SQL where clause.
+	 * Since this function is used internally and possibly by theme and plugin developers only,
+	 * it is expected that the field name is not vulnerable to SQL injection.
+	 */
+	public static function getSQLWhere(bool $include, string $field, array $values) {
+		$sqlWhere = ' and ' . $field;
+		if ( !$include ) $sqlWhere .= ' not';
+		$sqlWhere .= ' in (';
+		$sep = '';
+		foreach ($values as $value) {
+			$sqlWhere .= $sep . "'" . esc_sql($value) . "'";
+			$sep = ', ';
+		}
+		$sqlWhere .= ')';
+	}
+
+}
diff --git a/app/Views/listing.php b/app/Views/listing.php
index 31e0c5c..b815427 100644
--- a/app/Views/listing.php
+++ b/app/Views/listing.php
@@ -89,14 +89,17 @@
 
 	<div data-nestedpages-error class="updated error notice is-dismissible" style="display:none;"><p></p><button type="button" class="notice-dismiss"><span class="screen-reader-text"><?php esc_html_e('Dismiss this notice.', 'wp-nested-pages'); ?></span></button></div>
 
-	<?php include(NestedPages\Helpers::view('partials/tool-list')); ?>
+	<?php
+	include(NestedPages\Helpers::view('partials/tool-list'));
+	?>
 
 	<div id="np-error" class="updated error" style="clear:both;display:none;"></div>
 
 
 	<div class="nestedpages">
-		<?php $this->getPosts(); ?>
-		
+		<?php
+		$this->printPostsList();
+		?>
 		<div class="quick-edit quick-edit-form np-inline-modal" style="display:none;">
 			<?php include( NestedPages\Helpers::view('forms/quickedit-post') ); ?>
 		</div>
@@ -122,4 +125,4 @@
 if ( $this->listing_repo->showLinks($this->post_type, $this->user) ) include( NestedPages\Helpers::view('forms/link-form') );
 include( NestedPages\Helpers::view('forms/bulk-add') );
 include( NestedPages\Helpers::view('forms/delete-confirmation-modal') ); 
-if ( $this->integrations->plugins->wpml->installed ) include( NestedPages\Helpers::view('partials/wpml-translations') );
\ No newline at end of file
+if ( $this->integrations->plugins->wpml->installed ) include( NestedPages\Helpers::view('partials/wpml-translations') );
diff --git a/app/Views/partials/tool-list.php b/app/Views/partials/tool-list.php
index 5451db9..f5942ab 100644
--- a/app/Views/partials/tool-list.php
+++ b/app/Views/partials/tool-list.php
@@ -2,10 +2,17 @@
 $trashedCount = $this->post_repo->trashedCount($this->post_type->name); 
 $searchLabel = esc_attr($this->post_type->labels->search_items);
 
+$page_group_id = null;
+if ( array_key_exists( 'np_page_group', $_REQUEST ) ) {
+		if ( is_numeric( $_REQUEST['np_page_group'] ) )
+				$page_group_id = $_REQUEST['np_page_group'];
+}
+
 // WPML
 $wpml = $this->integrations->plugins->wpml->installed;
 if ( $wpml ) $current_lang = $this->integrations->plugins->wpml->getCurrentLanguage('name');
 if ( $wpml && $current_lang ) $searchLabel .= ' (' . $this->integrations->plugins->wpml->getCurrentLanguage('name') . ')';
+$current_language_short = $this->integrations->plugins->wpml->installed ? $this->integrations->plugins->wpml->getCurrentLanguage() : '';
 ?>
 <div class="nestedpages-tools">
 
@@ -142,7 +149,47 @@
 						echo $out;
 					endif;
 				endforeach;
+			// Page groups
 			?>
+			<div class="select" id="wp-nested-pages-tools-pagegroup">
+				<input type="hidden" name="lang" value="<?= $current_language_short ?>">
+				<select id="wp-nested-pages-select-pagegroup" name="np_page_group">
+					<option value="na">[ <?= esc_attr__('Select an item', 'wp-nested-pages') ?> ]</option>
+<?php
+				$options = [];
+				foreach ( $this->page_groups as $post ) {
+					$options[$post->ID] = $post->post_title;
+				}
+				if ( class_exists('Collator') ) {
+					$lang = $this->integrations->plugins->wpml->installed ? $this->integrations->plugins->wpml->getCurrentLanguage('code') : get_locale();
+					echo '<!-- ' . $lang . ' -->';
+					$coll = new \Collator($lang);
+					$coll->asort($options);
+				} else {
+					echo '<!-- uasort -->';
+					uasort($options, 'strnatcasecmp');
+				}
+				$all_languages = $current_language_short == 'all';
+				foreach ( $options as $post_id => $post_title ):
+?>
+					<option value="<?= $post_id ?>" <?php
+					if ( $page_group_id !== null ):
+						if ( $post_id == $page_group_id ) echo ' selected';
+					endif;
+?>><?php
+					echo esc_html($post_title);
+					if ( $this->integrations->plugins->wpml->installed && $all_languages ) {
+						$post_language = $this->integrations->plugins->wpml->getPostLanguage($post_id);
+						if ( $post_language !== null ) echo ' [' . $post_language . ']';
+					}
+?>
+					</option>
+<?php
+				endforeach;
+?>
+				</select>
+			</div>
+
 			<div class="select">
 				<input type="hidden" name="action" value="npListingSort">
 				<input type="hidden" name="page" value="<?php echo $this->pageURL(); ?>">
diff --git a/app/Views/settings/settings-general.php b/app/Views/settings/settings-general.php
index 565fca4..1998d82 100644
--- a/app/Views/settings/settings-general.php
+++ b/app/Views/settings/settings-general.php
@@ -31,6 +31,10 @@
 						<input type="checkbox" name="nestedpages_ui[non_indent]" value="true" <?php if ( $this->settings->nonIndentEnabled() ) echo 'checked'; ?> />
 						<?php _e('Use the classic (non-indented) hierarchy display.', 'wp-nested-pages'); ?>
 					</label></p>
+					<p><label>
+						<input type="number" name="nestedpages_ui[max_nonselected_pagegroups]" value="<?= esc_html($this->settings->maxNonSelectedPageGroups()) ?>" min="-1" max="10" style="max-width: 5rem">
+						<?php _e('Maximum number of page groups before selection is required (-1 through 10).', 'wp-nested-pages'); ?>
+					</label></p>
 				</div>
 			</div><!-- .row -->
 
@@ -173,4 +177,4 @@
 		</div><!-- .inner -->
 	</div><!-- .nestedpages-settings-table -->
 
-</div><!-- .nestedpages-general-wrapper -->
\ No newline at end of file
+</div><!-- .nestedpages-general-wrapper -->
diff --git a/composer.json b/composer.json
index e885f74..03566b4 100644
--- a/composer.json
+++ b/composer.json
@@ -19,5 +19,10 @@
 		"psr-4" : {
 			"NestedPages\\" : "app/"
 		}
+	},
+	"config": {
+		"allow-plugins": {
+			"composer/installers": true
+		}
 	}
 }