diff --git entityreference_view_widget/entityreference_view_widget.module entityreference_view_widget/entityreference_view_widget.module
index 9bcef5a..197da3a 100644
--- entityreference_view_widget/entityreference_view_widget.module
+++ entityreference_view_widget/entityreference_view_widget.module
@@ -208,14 +208,22 @@ function entityreference_view_widget_field_widget_form(&$form, &$form_state, $fi
   $target_view = explode('|', $widget['settings']['view']);
   $view = views_get_view($target_view[0]);
   $view->set_display($target_view[1]);
+
+  // Get the element values.
+  // Cope with nested data within sub-field_collections, etc.
+  $ajax = FALSE;
+  if (!empty($form_state['values'])) {
+    $field_parents = $element['#field_parents'];
+    $parents = array_merge($field_parents, array($field_name));
+    $element_values = drupal_array_get_nested_value($form_state['values'], $parents, $ajax);
+  }
+
   // If the widget has been rebuilt via #ajax, change the exposed filter and
   // pager values, if needed.
-  $ajax = isset($form_state['values'][$field_name][$field_language]);
   if ($ajax) {
-    $values = $form_state['values'][$field_name];
     // Set exposed_raw_input and exposed_data just like views_exposed_form_submit() does.
-    if (!empty($values['exposed_filters'])) {
-      $exposed_input = $values['exposed_filters'];
+    if (!empty($element_values['exposed_filters'])) {
+      $exposed_input = $element_values['exposed_filters'];
       $view->exposed_raw_input = $exposed_input;
       $view->exposed_data = $exposed_input;
       // Also set exposed_input, to prevent get_exposed_input() from using the
@@ -226,8 +234,8 @@ function entityreference_view_widget_field_widget_form(&$form, &$form_state, $fi
 
     // Only change the page if the rebuild wasn't triggered by an exposed filter,
     // and the page param is properly formatted.
-    if (isset($values['page']) && is_numeric($values['page']) && empty($form_state['triggering_element']['#exposed_filter'])) {
-      $view->set_current_page($values['page']);
+    if (isset($element_values['page']) && is_numeric($element_values['page']) && empty($form_state['triggering_element']['#exposed_filter'])) {
+      $view->set_current_page($element_values['page']);
     }
   }
   // Pass the selected entity ids as the first argument, if needed.
@@ -253,14 +261,14 @@ function entityreference_view_widget_field_widget_form(&$form, &$form_state, $fi
     '#markup' => $output,
   );
   if (!empty($view->exposed_widgets)) {
-    $element['filters'] = entityreference_view_widget_prepare_filters($view->exposed_widgets, $field_name);
+    $element['filters'] = entityreference_view_widget_prepare_filters($view->exposed_widgets, $field_name, $field_parents);
   }
 
   // Add a hidden form element to hold the current pager value.
   $element['page'] = array(
     // Set the parents above $field_language, so that the value doesn't get wiped
     // in entityreference_view_widget_validate.
-    '#parents' =>  array($field_name, 'page'),
+    '#parents' =>  array_merge($element['#field_parents'], array($field_name, 'page')),
     '#type' => 'hidden',
     '#attributes' => array(
       'class' => array('entityreference-view-widget-page'),
@@ -271,20 +279,22 @@ function entityreference_view_widget_field_widget_form(&$form, &$form_state, $fi
   // #ajax button is added, then when a pager link is clicked, a piece of JS code
   // sets the hidden page field (defined above) and simulates a click of the
   // button (defined below).
+  $path = empty($element['#field_parents']) ? $field_name : implode('/', $element['#field_parents']) . '/' . $field_name;
+  $wrapper = empty($element['#field_parents']) ? $field_name : implode('-', $element['#field_parents']) . '-' . $field_name;
   $element['pager_submit'] = array(
     '#type' => 'button',
     '#name' => 'pager_submit',
     '#attributes' => array('class' => array('pager-submit')),
     '#ajax' => array(
-      'path' => 'entityreference_view_widget/ajax/' . $field_name,
-      'wrapper' => 'edit-' . str_replace('_', '-', $field_name),
+      'path' => 'entityreference_view_widget/ajax/' . $path,
+      'wrapper' => 'edit-' . str_replace('_', '-', $wrapper),
       'method' => 'replace',
       'progress' => array(
         'type' => 'throbber',
         'message' => '',
       ),
     ),
-    '#limit_validation_errors' => array(array($field_name)),
+    '#limit_validation_errors' => array(array_merge($element['#field_parents'], array($field_name))),
     '#weight' => 100,
     '#submit' => array('entityreference_view_widget_exposed_filters_pager_submit'),
   );
@@ -296,12 +306,14 @@ function entityreference_view_widget_field_widget_form(&$form, &$form_state, $fi
       $entity_view = entity_view($entity_type, $selected_entities, 'entityreference_view_widget');
       $entity_view = reset($entity_view);
       $i = 0;
+      $path = empty($element['#field_parents']) ? $field_name : implode('/', $element['#field_parents']) . '/' . $field_name;
+      $wrapper = empty($element['#field_parents']) ? $field_name : implode('-', $element['#field_parents']) . '-' . $field_name;
       foreach ($selected_entities as $entity_id => $entity) {
         // Remove the checkbox placeholder, it's not needed in this context.
         unset($entity_view[$entity_id]['entityreference_view_widget_action']);
 
         $entity_view[$entity_id]['_weight'] = array(
-          '#parents' =>  array($field_name, $field_language, 'items', $entity_id, '_weight'),
+          '#parents' =>  array_merge($element['#field_parents'], array($field_name, $field_language, 'items', $entity_id, '_weight')),
           '#type' => 'weight',
           '#title' => t('Weight for @title', array('@title' => entity_label($entity_type, $entity))),
           '#title_display' => 'invisible',
@@ -309,14 +321,14 @@ function entityreference_view_widget_field_widget_form(&$form, &$form_state, $fi
           '#default_value' => $i,
         );
         $entity_view[$entity_id]['remove'] = array(
-          '#parents' =>  array($field_name, $field_language, 'items', $entity_id, 'remove'),
+          '#parents' =>  array_merge($element['#field_parents'], array($field_name, $field_language, 'items', $entity_id, 'remove')),
           '#type' => 'checkbox',
           '#title' => t('Remove'),
           '#weight' => -10,
           '#refresh_items' => TRUE,
           '#ajax' => array(
-            'path' => 'entityreference_view_widget/ajax/' . $field_name,
-            'wrapper' => 'edit-' . str_replace('_', '-', $field_name),
+            'path' => 'entityreference_view_widget/ajax/' . $path,
+            'wrapper' => 'edit-' . str_replace('_', '-', $wrapper),
             'method' => 'replace',
             'progress' => array(
               'type' => 'throbber',
@@ -341,6 +353,8 @@ function entityreference_view_widget_field_widget_form(&$form, &$form_state, $fi
   // displayed through the view.
   $substitutions = array();
   $result_entities = $view->query->get_result_entities($view->result);
+  $path = empty($element['#field_parents']) ? $field_name : implode('/', $element['#field_parents']) . '/' . $field_name;
+  $wrapper = empty($element['#field_parents']) ? $field_name : implode('-', $element['#field_parents']) . '-' . $field_name;
   foreach ($result_entities[1] as $row_id => $entity) {
     $entity_id = entity_id($entity_type, $entity);
     if (!$view->display_handler->options['hide_left']) {
@@ -348,8 +362,8 @@ function entityreference_view_widget_field_widget_form(&$form, &$form_state, $fi
         '#type' => 'checkbox',
         '#refresh_items' => TRUE,
         '#ajax' => array(
-          'path' => 'entityreference_view_widget/ajax/' . $field_name,
-          'wrapper' => 'edit-' . str_replace('_', '-', $field_name),
+          'path' => 'entityreference_view_widget/ajax/' . $path,
+          'wrapper' => 'edit-' . str_replace('_', '-', $wrapper),
           'method' => 'replace',
           'progress' => array(
             'type' => 'throbber',
@@ -463,8 +477,19 @@ function theme_entityreference_view_widget_selected_items($variables) {
 function entityreference_view_widget_validate($element, &$form_state) {
   $field_name = $element['#field_name'];
   $language = $element['#language'];
-  $target_type = $form_state['field'][$field_name][$language]['field']['settings']['target_type'];
-  $element_values = $form_state['values'][$field_name][$language];
+  $target_bundle = $element['#bundle'];
+  $field_parents = $element['#field_parents'];
+
+  // Cope with nested data within sub-field_collections, etc.
+  $parents = array_merge($field_parents, array($field_name, $language));
+  $element_values = drupal_array_get_nested_value($form_state['values'], $parents);
+
+  $parents = array_merge(array($field_name, $language, 'field', 'settings', 'target_type'));
+  $target_type = drupal_array_get_nested_value($form_state['field'], $parents);
+  if (!empty($field_parents)) {
+    $parents = array_merge(array('#parents'), $field_parents, array('#fields', $field_name, $language, 'field', 'settings', 'target_type'));
+    $target_type = drupal_array_get_nested_value($form_state['field'], $parents);
+  }
 
   $value = array();
   // First add the existing elements, if they are not marked for deletion.
@@ -489,10 +514,9 @@ function entityreference_view_widget_validate($element, &$form_state) {
   form_set_value($element, $value, $form_state);
 
   // Update items.
-  $parents = array_slice($element['#parents'], 0, -2);
-  $field_state = field_form_get_state($parents, $field_name, $language, $form_state);
+  $field_state = field_form_get_state($field_parents, $field_name, $language, $form_state);
   $field_state['items'] = $value;
-  field_form_set_state($parents, $field_name, $language, $form_state, $field_state);
+  field_form_set_state($field_parents, $field_name, $language, $form_state, $field_state);
 }
 
 function entityreference_view_widget_exposed_filters_validate($element, &$form_state) {
@@ -508,7 +532,7 @@ function entityreference_view_widget_exposed_filters_validate($element, &$form_s
  * Prepare the form containing exposed views filters for functioning
  * as a part of the widget form (validation, #ajax, #parents...).
  */
-function entityreference_view_widget_prepare_filters($form, $field_name) {
+function entityreference_view_widget_prepare_filters($form, $field_name, $field_parents) {
   // $form will be a string if the user failed to select our exposed plugin style plugin.
   if (!is_array($form)) {
     return;
@@ -516,15 +540,17 @@ function entityreference_view_widget_prepare_filters($form, $field_name) {
 
   $form['#element_validate'] = array('entityreference_view_widget_exposed_filters_validate');
   $form['submit']['#submit'] = array('entityreference_view_widget_exposed_filters_submit');
-  $form['submit']['#limit_validation_errors'] = array(array($field_name));
+  $form['submit']['#limit_validation_errors'] = array(array_merge($field_parents, array($field_name)));
   $form['submit']['#name'] = 'apply-' . $field_name;
 
   foreach (element_get_visible_children($form) as $key) {
-    $form[$key]['#parents'] = array($field_name, 'exposed_filters', $key);
+    $form[$key]['#parents'] = array_merge($field_parents, array($field_name, 'exposed_filters', $key));
     $form[$key]['#exposed_filter'] = TRUE;
     if (!empty($form[$key]['#ajax']) && empty($form[$key]['#ajax']['path']) && empty($form[$key]['#ajax']['callback'])) {
-      $form[$key]['#ajax']['path'] = 'entityreference_view_widget/ajax/' . $field_name;
-      $form[$key]['#ajax']['wrapper'] = 'edit-' . str_replace('_', '-', $field_name);
+      $path = empty($field_parents) ? $field_name : implode('/', $field_parents) . '/' . $field_name;
+      $wrapper = empty($field_parents) ? $field_name : implode('-', $field_parents) . '-' . $field_name;
+      $form[$key]['#ajax']['path'] = 'entityreference_view_widget/ajax/' . $path;
+      $form[$key]['#ajax']['wrapper'] = 'edit-' . str_replace('_', '-', $wrapper);
     }
   }
   return $form;