diff --git a/README.txt b/README.txt
index 7dc7d6c..a2e99dd 100644
--- a/README.txt
+++ b/README.txt
@@ -10,7 +10,7 @@ results. Additionally, using meta tags can help control the summary content
 that is used within social networks when visitors link to your site,
 particularly the Open Graph submodule for use with Facebook (see below).
 
-This version of the module only works with Drupal 7.x.
+This version of the module only works with Drupal 7.15 and newer.
 
 
 Features
diff --git a/metatag.entity_translation.inc b/metatag.entity_translation.inc
deleted file mode 100644
index ac9dd87..0000000
--- a/metatag.entity_translation.inc
+++ /dev/null
@@ -1,53 +0,0 @@
-<?php
-/**
- * @file
- * Meta Tags implementation of Entity Translation hooks.
- */
-
-/**
- * Implements hook_entity_translation_insert().
- */
-function metatag_entity_translation_insert($entity_type, $entity, $translation, $values = array()) {
-  // The update hook can handle both cases so just call that one.
-  metatag_entity_translation_update($entity_type, $entity, $translation, $values);
-}
-
-/**
- * Implements hook_entity_translation_update().
- */
-function metatag_entity_translation_update($entity_type, $entity, $translation, $values = array()) {
-  // Get the ID of the entity.
-  list($entity_id) = entity_extract_ids($entity_type, $entity);
-
-  // Grab the meta tag data only; we don't need anything else.
-  $values = isset($values['metatags']) ? $values['metatags'] : array();
-
-  // Set the default values to be that of the entity's original language (whose
-  // tags are shown if the current language has none set) so that we can
-  // extract these from the form elements if they haven't been changed.
-  $entity_language = function_exists('entity_language') ?
-    entity_language($entity_type, $entity) : $entity->language;
-  if ($entity_language && isset($entity->metatags[$entity_language])) {
-    $defaults = $entity->metatags[$entity_language];
-  }
-  else {
-    $defaults = array();
-  }
-
-  // Remove all of the defaults.
-  metatag_filter_values_from_defaults($values, $defaults);
-
-  // Save the new data.
-  metatag_metatags_save($entity_type, $entity_id, $values, $translation['language']);
-}
-
-/**
- * Implements hook_entity_translation_delete().
- */
-function metatag_entity_translation_delete($entity_type, $entity, $langcode) {
-  // Get the entity's ID.
-  list($entity_id) = entity_extract_ids($entity_type, $entity);
-
-  // Delete the translation.
-  metatag_metatags_delete($entity_type, $entity_id, $langcode);
-}
diff --git a/metatag.info b/metatag.info
index 654772f..4b65553 100644
--- a/metatag.info
+++ b/metatag.info
@@ -2,8 +2,14 @@ name = Meta tags
 description = "Adds support and an API to implement meta tags."
 package = Meta tags
 core = 7.x
-dependencies[] = token
+
+# This requires Drupal 7.15 or newer.
+dependencies[] = system (>=7.15)
+
+# CTools and Token are also required.
 dependencies[] = ctools
+dependencies[] = token
+
 configure = admin/config/search/metatags
 
 files[] = metatag.inc
diff --git a/metatag.install b/metatag.install
index 0a99f84..b1fc213 100644
--- a/metatag.install
+++ b/metatag.install
@@ -112,9 +112,19 @@ function metatag_requirements($phase) {
       list($minor, $suffix) = explode('-', $minor);
     }
 
+    // Releases of Drupal older than 7.15 did not have entity_language(), which
+    // is now required.
+    if ($minor < 15) {
+      $requirements['metatag'] = array(
+        'severity' => REQUIREMENT_WARNING,
+        'title' => 'Metatag',
+        'value' => $t('Upgrade Drupal core to v7.15 or newer'),
+        'description' => $t("This older version of Drupal core is missing functionality necessary for the module's multilingual support, it must be upgraded to at least version 7.15."),
+      );
+    }
     // Releases of Drupal older than 7.17 did not trigger hook_entity_view on
     // term pages, so recommend updating.
-    if ($minor < 17) {
+    elseif ($minor < 17) {
       $requirements['metatag'] = array(
         'severity' => REQUIREMENT_WARNING,
         'title' => 'Metatag',
@@ -122,6 +132,7 @@ function metatag_requirements($phase) {
         'description' => $t('Your older version of Drupal core is missing functionality necessary for taxonomy term pages to work correctly, it is strongly recommended to upgrade to the latest release.'),
       );
     }
+    // Everything's OK.
     else {
       $requirements['metatag'] = array(
         'severity' => REQUIREMENT_OK,
diff --git a/metatag.module b/metatag.module
index f94f4fe..ac29e6f 100644
--- a/metatag.module
+++ b/metatag.module
@@ -4,11 +4,6 @@
  * @todo Add revisionable support for metatag data.
  */
 
-// Load the translation functionality when appropriate.
-if (module_exists('entity_translation')) {
-  include_once dirname(__FILE__) . '/metatag.entity_translation.inc';
-}
-
 /**
  * Implements hook_help().
  */
@@ -373,10 +368,9 @@ function metatag_metatags_load_multiple($type, array $ids) {
  *   The language of the translation set
  */
 function metatag_metatags_save($type, $id, $metatags, $language) {
-  // Use the default content language if the entity doesn't have language
-  // support.
+  // If no language assigned, use the has-no-language language.
   if (!$language) {
-    $language = $GLOBALS['language_content']->language;
+    $language = LANGUAGE_NONE;
   }
 
   // Check that $id is numeric because of Entity API and string IDs.
@@ -530,9 +524,8 @@ function metatag_entity_insert($entity, $entity_type) {
   if (isset($entity->metatags)) {
     list($id) = entity_extract_ids($entity_type, $entity);
 
-    // Determine the language as per http://drupal.org/node/1626346.
-    $language = function_exists('entity_language') ?
-      entity_language($entity_type, $entity) : $entity->language;
+    // Determine the entity's language.
+    $language = metatag_entity_get_language($entity_type, $entity);
 
     metatag_metatags_save($entity_type, $id, $entity->metatags, $language);
   }
@@ -542,19 +535,34 @@ function metatag_entity_insert($entity, $entity_type) {
  * Implements hook_entity_update().
  */
 function metatag_entity_update($entity, $entity_type) {
-  list($id) = entity_extract_ids($entity_type, $entity);
+  list($entity_id) = entity_extract_ids($entity_type, $entity);
 
   if (isset($entity->metatags)) {
+    // Determine the entity's language.
+    $new_language = metatag_entity_get_language($entity_type, $entity);
+
+    // Determine the language for this entity object.
+    if (isset($entity->original)) {
+      $old_language = metatag_entity_get_language($entity_type, $entity->original);
+
+      // If the language has changed then remove the old one. When a new
+      // translation is being saved using Entity Translation both values will
+      // be the same, so this is safe to do.
+      if ($old_language != $new_language) {
+        db_delete('metatag')
+          ->condition('entity_type', $entity_type)
+          ->condition('entity_id', $entity_id)
+          ->condition('language', $old_language)
+          ->execute();
+      }
+    }
 
-    // Determine the language as per http://drupal.org/node/1626346.
-    $language = function_exists('entity_language') ?
-      entity_language($entity_type, $entity) : $entity->language;
-
-    metatag_metatags_save($entity_type, $id, $entity->metatags, $language);
+    // Save the record.
+    metatag_metatags_save($entity_type, $entity_id, $entity->metatags, $new_language);
   }
   else {
     // Still ensure the meta tag output is cached.
-    metatag_metatags_cache_clear($entity_type, $id);
+    metatag_metatags_cache_clear($entity_type, $entity_id);
   }
 }
 
@@ -596,9 +604,31 @@ function metatag_entity_view($entity, $entity_type, $view_mode, $langcode) {
       return;
     }
 
+    // Obbtain some details of the entity that are needed elsewhere.
     list($entity_id, $revision_id, $bundle) = entity_extract_ids($entity_type, $entity);
     $instance = "{$entity_type}:{$bundle}";
 
+    // Determine the language this entity actually uses.
+    $entity_language = metatag_entity_get_language($entity_type, $entity);
+
+    // The requested language is different to the entity's language, look for
+    // a language elsewhere.
+    if ($entity_language != $langcode) {
+      // If no language was defined for the entity then use that for the 
+      if ($entity_language == LANGUAGE_NONE) {
+        $langcode = LANGUAGE_NONE;
+      }
+      else {
+        $enabled_languages = field_content_languages();
+        foreach (field_language($entity_type, $entity) as $field => $lang) {
+          // Only accept actual language values that are properly enabled.
+          if ($lang != LANGUAGE_NONE && in_array($lang, $enabled_languages)) {
+            $langcode = $lang;
+          }
+        }
+      }
+    }
+
     // All applicable pieces for this current page.
     $cid_parts = array(
       'entity_type' => $entity_type,
@@ -618,12 +648,13 @@ function metatag_entity_view($entity, $entity_type, $view_mode, $langcode) {
     // hook_metatag_page_cache_cid_parts_alter().
     drupal_alter('metatag_page_cache_cid_parts', $cid_parts);
 
-    $cid = "output:{$entity_type}:{$entity_id}:" . hash('sha256', serialize($cid_parts));
+    $cid = "output:{$entity_type}:{$entity_id}:{$langcode}:" . hash('sha256', serialize($cid_parts));
 
     if ($cache = cache_get($cid, 'cache_metatag')) {
-      $entity->content['metatags'] = $cache->data;
+      $output = $cache->data;
     }
     else {
+      // Separate the meta tags.
       $metatags = isset($entity->metatags) ? $entity->metatags : array();
 
       // Build options for meta tag rendering.
@@ -635,7 +666,7 @@ function metatag_entity_view($entity, $entity_type, $view_mode, $langcode) {
 
       // Ensure we actually pass a language object rather than language code.
       $languages = language_list();
-      if (isset($langcode) && isset($languages[$langcode])) {
+      if (isset($languages[$langcode])) {
         $options['language'] = $languages[$langcode];
       }
 
@@ -646,13 +677,13 @@ function metatag_entity_view($entity, $entity_type, $view_mode, $langcode) {
       $options['entity'] = $entities[$entity_id];
 
       // Render the metatags and save to the cache.
-      $entity->content['metatags'] = metatag_metatags_view($instance, $metatags, $options);
-      cache_set($cid, $entity->content['metatags'], 'cache_metatag');
+      $output = metatag_metatags_view($instance, $metatags, $options);
+      cache_set($cid, $output, 'cache_metatag');
     }
 
     // We need to register the term's metatags, so we can later fetch them.
     // @see metatag_page_build().
-    metatag_page_set_metatags($instance, $entity->content['metatags']);
+    metatag_page_set_metatags($instance, $output);
   }
 }
 
@@ -681,25 +712,11 @@ function metatag_metatags_view($instance, array $metatags = array(), array $opti
 
   // If there are any tags, determine the translation to display.
   if (!empty($metatags)) {
-    // Get the display language.
-    if (isset($options['language']->language)) {
-      // Use the passed-in option.
-      $translation = $options['language']->language;
-    }
-    elseif (isset($metatags[$GLOBALS['language_content']->language])) {
-      // We weren't given a language; use the global content one.
-      $translation = $GLOBALS['language_content']->language;
-    }
-    else {
-      // The language is not defined.
-      $translation = LANGUAGE_NONE;
-    }
-
-    // Choose the derived translation, fail over to the language-agnostic
-    // values if applicable.
-    if (!empty($metatags[$translation])) {
-      $metatags = $metatags[$translation];
+    // Get the display language; default to the entity's language.
+    if (isset($options['language']) && isset($options['language']->language) && isset($metatags[$options['language']->language])) {
+      $metatags = $metatags[$options['language']->language];
     }
+    // If no language requested, use the no-language value.
     elseif (!empty($metatags[LANGUAGE_NONE])) {
       $metatags = $metatags[LANGUAGE_NONE];
     }
@@ -1146,45 +1163,41 @@ function metatag_field_attach_form($entity_type, $entity, &$form, &$form_state,
   if (!metatag_entity_has_metatags($entity_type, $entity)) {
     return;
   }
+  // Entity_Translation will trigger this hook again, skip it.
+  if (!empty($form_state['entity_translation']['is_translation'])) {
+    return;
+  }
 
   list($entity_id, $revision_id, $bundle) = entity_extract_ids($entity_type, $entity);
   $instance = "{$entity_type}:{$bundle}";
 
   // Grab the meta tags for display in the form if there are any.
-  if (isset($entity->metatags)) {
-
-    // Determine the entity language as per http://drupal.org/node/1626346.
-    $entity_language = function_exists('entity_language') ?
-      entity_language($entity_type, $entity) : $entity->language;
-
-    // Determine from where we should get the tags.
-    if (!(isset($entity->metatags[$langcode]) || isset($entity->metatags[$entity_language]))) {
+  if (!empty($entity->metatags)) {
+    // Identify the language to use with this entity.
+    $entity_language = metatag_entity_get_language($entity_type, $entity);
 
-      // This is a preview so set the tags to the raw submission data.  No
-      // language has been set.
-      $metatags = $entity->metatags;
+    // If this is a new translation using Entity Translation, load the meta
+    // tags from the entity's original language.
+    if (module_exists('entity_translation') && empty($form['#entity_translation_source_form']) && ($handler = entity_translation_entity_form_get_handler($form, $form_state)) && isset($entity->metatags[$handler->getSourceLanguage()])) {
+      $metatags = $entity->metatags[$handler->getSourceLanguage()];
     }
+    // Determine from where we should get the tags.
     elseif (isset($entity->metatags[$langcode])) {
       // Set the tags to the translation set matching that of the form.
       $metatags = $entity->metatags[$langcode];
-
-      // For tags that aren't set in the current form language, fill them in
-      // with default data from the original translation, the entity language.
-      if (isset($entity->metatags[$entity_language])) {
-        foreach ($entity->metatags[$entity_language] as $tag_id => $tag_data) {
-          if (!isset($metatags[$tag_id])) {
-            $metatags[$tag_id] = $tag_data;
-          }
-        }
-      }
     }
     // There is no translation for this entity's tags in the current
     // language. Instead, display tags in the language of the entity, the
     // source language of translations. The will provide translators with the
     // original text to translate.
-    else {
+    elseif (isset($entity->metatags[$entity_language])) {
       $metatags = $entity->metatags[$entity_language];
     }
+    // This is a preview so set the tags to the raw submission data.  No
+    // language has been set.
+    else {
+      $metatags = $entity->metatags;
+    }
   }
   else {
     $metatags = array();
@@ -1234,7 +1247,7 @@ function metatag_get_info($type = NULL, $name = NULL) {
   if (!isset($info)) {
     // hook_metatag_info() includes translated strings, so each language is cached
     // separately.
-    $cid = 'info:' . $GLOBALS['language']->language;
+    $cid = 'info:' . LANGUAGE_NONE;
 
     if ($cache = cache_get($cid, 'cache_metatag')) {
       $info = $cache->data;
@@ -1535,6 +1548,34 @@ function metatag_config_is_enabled($instance, $include_defaults = FALSE, $includ
 }
 
 /**
+ * Wrapper around entity_language() to use LANGUAGE_NONE if the entity does not
+ * have a language assigned.
+ *
+ * @param $entity_type
+ *   An entity type's machine name.
+ * @param $entity
+ *   The entity to review;
+ *
+ * @return
+ *   A string indicating the language code to be used.
+ */
+function metatag_entity_get_language($entity_type, $entity) {
+  // Determine the entity's language.
+  $langcode = entity_language($entity_type, $entity);
+
+  // If no matching language was found, which will happen for e.g. terms and
+  // users, it is normally recommended to use the system default language.
+  // However, as the system default language can change, this could potentially
+  // cause data loss / confusion problems; as a result use the system "no
+  // language" value to avoid any potential problems.
+  if (empty($langcode)) {
+    $langcode = LANGUAGE_NONE;
+  }
+
+  return $langcode;
+}
+
+/**
  * Implements of hook_features_api().
  */
 function metatag_features_api() {
@@ -1613,3 +1654,18 @@ function metatag_ctools_render_alter(&$info, $page, $context) {
     }
   }
 }
+
+/**
+ * Implements hook_entity_translation_delete().
+ *
+ * Required for content translations being handled via Entity_Translation to
+ * remove the appropriate record when a translation is removed without the
+ * corresponding entity record also being removed.
+ */
+function metatag_entity_translation_delete($entity_type, $entity, $langcode) {
+  // Get the entity's ID.
+  list($entity_id) = entity_extract_ids($entity_type, $entity);
+  
+  // Delete the translation.
+  metatag_metatags_delete($entity_type, $entity_id, $langcode);
+}