diff --git a/lib/classes/task/delete_incomplete_users_task.php b/lib/classes/task/delete_incomplete_users_task.php
index 0fb84b822c0..dda16f7ec66 100644
--- a/lib/classes/task/delete_incomplete_users_task.php
+++ b/lib/classes/task/delete_incomplete_users_task.php
@@ -59,6 +59,10 @@ class delete_incomplete_users_task extends scheduled_task {
                 if (isguestuser($user) or is_siteadmin($user)) {
                     continue;
                 }
+                if ($user->lastname !== '' and $user->firstname !== '' and $user->email !== '') {
+                    // This can happen on MySQL - see MDL-52831.
+                    continue;
+                }
                 delete_user($user);
                 mtrace(" Deleted not fully setup user $user->username ($user->id)");
             }
diff --git a/login/signup_form.php b/login/signup_form.php
index a463e9d77ea..45966f62379 100644
--- a/login/signup_form.php
+++ b/login/signup_form.php
@@ -112,6 +112,11 @@ class login_signup_form extends moodleform {
     function definition_after_data(){
         $mform = $this->_form;
         $mform->applyFilter('username', 'trim');
+
+        // Trim required name fields.
+        foreach (useredit_get_required_name_fields() as $field) {
+            $mform->applyFilter($field, 'trim');
+        }
     }
 
     function validation($data, $files) {
diff --git a/user/edit_form.php b/user/edit_form.php
index 721b538c2f2..3eb12c88df9 100644
--- a/user/edit_form.php
+++ b/user/edit_form.php
@@ -99,6 +99,11 @@ class user_edit_form extends moodleform {
         $mform = $this->_form;
         $userid = $mform->getElementValue('id');
 
+        // Trim required name fields.
+        foreach (useredit_get_required_name_fields() as $field) {
+            $mform->applyFilter($field, 'trim');
+        }
+
         if ($user = $DB->get_record('user', array('id' => $userid))) {
 
             // Remove description.
diff --git a/user/editadvanced_form.php b/user/editadvanced_form.php
index 2dad585bfc1..b68992305ef 100644
--- a/user/editadvanced_form.php
+++ b/user/editadvanced_form.php
@@ -140,6 +140,12 @@ class user_editadvanced_form extends moodleform {
         global $USER, $CFG, $DB, $OUTPUT;
 
         $mform = $this->_form;
+
+        // Trim required name fields.
+        foreach (useredit_get_required_name_fields() as $field) {
+            $mform->applyFilter($field, 'trim');
+        }
+
         if ($userid = $mform->getElementValue('id')) {
             $user = $DB->get_record('user', array('id' => $userid));
         } else {
diff --git a/user/editlib.php b/user/editlib.php
index ae9504d840b..5051f76899d 100644
--- a/user/editlib.php
+++ b/user/editlib.php
@@ -284,11 +284,17 @@ function useredit_shared_definition(&$mform, $editoroptions, $filemanageroptions
     }
 
     $strrequired = get_string('required');
+    $stringman = get_string_manager();
 
     // Add the necessary names.
     foreach (useredit_get_required_name_fields() as $fullname) {
         $mform->addElement('text', $fullname,  get_string($fullname),  'maxlength="100" size="30"');
-        $mform->addRule($fullname, $strrequired, 'required', null, 'client');
+        if ($stringman->string_exists('missing'.$fullname, 'core')) {
+            $strmissingfield = get_string('missing'.$fullname, 'core');
+        } else {
+            $strmissingfield = $strrequired;
+        }
+        $mform->addRule($fullname, $strmissingfield, 'required', null, 'client');
         $mform->setType($fullname, PARAM_NOTAGS);
     }
 
diff --git a/user/tests/behat/name_fields.feature b/user/tests/behat/name_fields.feature
new file mode 100644
index 00000000000..ab615123581
--- /dev/null
+++ b/user/tests/behat/name_fields.feature
@@ -0,0 +1,50 @@
+@core @core_user
+Feature: Both first name and surname are always available for every user
+  In order to easily identify and display users on Moodle pages
+  As any user
+  I need to rely on both first name and surname are always available
+
+  Scenario: Attempting to self-register as a new user with empty names
+    Given the following config values are set as admin:
+      | registerauth    | email |
+      | passwordpolicy  | 0     |
+    And I am on site homepage
+    And I follow "Log in"
+    And I follow "New Account"
+    When I set the following fields to these values:
+      | Username      | mrwhitespace        |
+      | Password      | Gue$$m3ifY0uC&n     |
+      | Email address | mrwhitespace@nas.ty |
+      | Email (again) | mrwhitespace@nas.ty |
+    And I set the field "First name" to " "
+    And I set the field "Surname" to " "
+    And I click on "Create my new account" "button"
+    Then I should see "Missing given name"
+    And I should see "Missing surname"
+
+  Scenario: Attempting to change own names to whitespace
+    Given the following "users" exist:
+      | username | firstname | lastname | email       |
+      | foobar   | Foo       | Bar      | foo@bar.com |
+    And I log in as "foobar"
+    And I follow "Profile" in the user menu
+    And I follow "Edit profile"
+    When I set the field "First name" to " "
+    And I set the field "Surname" to " "
+    And I click on "Update profile" "button"
+    Then I should see "Missing given name"
+    And I should see "Missing surname"
+
+  Scenario: Attempting to change someone else's names to whitespace
+    Given the following "users" exist:
+      | username | firstname | lastname | email       |
+      | foobar   | Foo       | Bar      | foo@bar.com |
+    And I log in as "admin"
+    And I navigate to "Browse list of users" node in "Site administration > Users > Accounts"
+    And I follow "Foo Bar"
+    And I follow "Edit profile"
+    When I set the field "First name" to " "
+    And I set the field "Surname" to " "
+    And I click on "Update profile" "button"
+    Then I should see "Missing given name"
+    And I should see "Missing surname"