diff --git a/src/Plugin/Block/ArchiveTreeBlock.php b/src/Plugin/Block/ArchiveTreeBlock.php
index 9af9e79..d0f3ea3 100644
--- a/src/Plugin/Block/ArchiveTreeBlock.php
+++ b/src/Plugin/Block/ArchiveTreeBlock.php
@@ -3,6 +3,9 @@
 namespace Drupal\archive_tree\Plugin\Block;
 
 use Drupal\Core\Block\BlockBase;
+use Drupal\Core\Form\FormStateInterface;
+use Drupal\node\Entity\NodeType;
+
 
 /**
  * Provides an 'Archive tree' block.
@@ -12,21 +15,35 @@ use Drupal\Core\Block\BlockBase;
  *   admin_label = @Translation("Archive tree"),
  * )
  */
-use Drupal\Core\Block\BlockForm;
-use Drupal\Core\Form\FormStateInterface;
 
 class ArchiveTreeBlock extends BlockBase {
   /**
    * {@inheritdoc}
    */
+
   public function defaultConfiguration() {
     return [
       'expand_years' => FALSE,
+      'content_types' => ['article'],
     ] + parent::defaultConfiguration();
   }
 
+
   public function blockForm($form, FormStateInterface $form_state) {
     $form = parent::blockForm($form, $form_state);
+    $types = NodeType::loadMultiple();
+    $options = [];
+    foreach ($types as $type) {
+      $options[$type->id()] = $type->label();
+    }
+    $form['content_types'] = [
+      '#type' => 'checkboxes',
+      '#title' => $this->t('Content types to include'),
+      '#options' => $options,
+      '#default_value' => $this->configuration['content_types'],
+      '#description' => $this->t('Select one or more content types to include in the archive tree.'),
+      '#required' => TRUE,
+    ];
     $form['expand_years'] = [
       '#type' => 'checkbox',
       '#title' => $this->t('Expand all years by default'),
@@ -36,15 +53,25 @@ class ArchiveTreeBlock extends BlockBase {
     return $form;
   }
 
+
   public function blockSubmit($form, FormStateInterface $form_state) {
     parent::blockSubmit($form, $form_state);
     $this->configuration['expand_years'] = $form_state->getValue('expand_years');
+    $selected_types = array_filter($form_state->getValue('content_types'));
+    $this->configuration['content_types'] = $selected_types;
   }
 
   public function build() {
     $storage = \Drupal::entityTypeManager()->getStorage('node');
+    $types = array_filter($this->configuration['content_types']);
+    if (empty($types)) {
+      // If no types selected, return empty block.
+      return [
+        '#markup' => $this->t('No content types selected.'),
+      ];
+    }
     $query = $storage->getQuery()
-      ->condition('type', 'article')
+      ->condition('type', $types, 'IN')
       ->condition('status', 1)
       ->sort('created', 'DESC')
       ->accessCheck(TRUE);