diff --git a/mod/glossary/tests/behat/behat_mod_glossary.php b/mod/glossary/tests/behat/behat_mod_glossary.php
new file mode 100644
index 00000000000..4d272685cab
--- /dev/null
+++ b/mod/glossary/tests/behat/behat_mod_glossary.php
@@ -0,0 +1,58 @@
+<?php
+// This file is part of Moodle - http://moodle.org/
+//
+// Moodle is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// Moodle is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with Moodle.  If not, see <http://www.gnu.org/licenses/>.
+
+/**
+ * Steps definitions related with the glossary activity.
+ *
+ * @package    mod_glossary
+ * @category   test
+ * @copyright  2013 David Monllaó
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+
+// NOTE: no MOODLE_INTERNAL test here, this file may be required by behat before including /config.php.
+
+require_once(__DIR__ . '/../../../../lib/behat/behat_base.php');
+
+use Behat\Behat\Context\Step\Given as Given,
+    Behat\Gherkin\Node\TableNode as TableNode,
+    Behat\Mink\Exception\ElementNotFoundException as ElementNotFoundException;
+
+/**
+ * Glossary-related steps definitions.
+ *
+ * @package    mod_glossary
+ * @category   test
+ * @copyright  2013 David Monllaó
+ * @license    http://www.gnu.org/copyleft/gpl.html GNU GPL v3 or later
+ */
+class behat_mod_glossary extends behat_base {
+
+    /**
+     * Adds an entry to the current glossary with the provided data. You should be in the glossary page.
+     *
+     * @Given /^I add a glossary entry with the following data:$/
+     * @param TableNode $data
+     */
+    public function i_add_a_glossary_entry_with_the_following_data(TableNode $data) {
+        return array(
+            new Given('I press "' . get_string('addentry', 'mod_glossary') . '"'),
+            new Given('I fill the moodle form with:', $data),
+            new Given('I press "Save changes"')
+        );
+    }
+
+}
diff --git a/mod/glossary/tests/behat/prevent_duplicate_entries.feature b/mod/glossary/tests/behat/prevent_duplicate_entries.feature
new file mode 100644
index 00000000000..196d220982e
--- /dev/null
+++ b/mod/glossary/tests/behat/prevent_duplicate_entries.feature
@@ -0,0 +1,36 @@
+@mod_glossary
+Feature: A teacher can choose whether to allow duplicate entries in a glossary
+  In order to avoid confusion
+  As a moodle teacher
+  I need to avoid having duplicate concept definitions
+
+  @javascript
+  Scenario: Prevent duplicate entries
+    Given the following "users" exists:
+      | username | firstname | lastname | email |
+      | teacher1 | Teacher | 1 | teacher1@asd.com |
+    And the following "courses" exists:
+      | fullname | shortname | category |
+      | Course 1 | C1 | 0 |
+    And the following "course enrolments" exists:
+      | user | course | role |
+      | teacher1 | C1 | editingteacher |
+    And I log in as "teacher1"
+    And I follow "Course 1"
+    And I turn editing mode on
+    And I add a "Glossary" to section "1" and I fill the form with:
+      | Name | Test glossary name |
+      | Description | Test glossary description |
+      | Duplicate entries allowed | No |
+    And I follow "Test glossary name"
+    And I add a glossary entry with the following data:
+      | Concept | Unique concept |
+      | Definition | I'm the definition of an unique concept |
+    When I press "Add a new entry"
+    And I fill the moodle form with:
+      | Concept | Unique concept |
+      | Definition | There is no definition restriction |
+    And I press "Save changes"
+    Then I should see "This concept already exists. No duplicates allowed in this glossary."
+    And I press "Cancel"
+