diff --git a/build/build.xml b/build/build.xml
index a86cb9c36b..5ea77bd9e1 100644
--- a/build/build.xml
+++ b/build/build.xml
@@ -67,7 +67,6 @@
 		<exec dir="."
 			command="phpBB/vendor/bin/phpunit
 			--log-junit build/logs/phpunit.xml
-			--configuration phpunit.xml.all
 			--group slow
 			--coverage-clover build/logs/clover-slow.xml
 			--coverage-html build/coverage-slow"
diff --git a/tests/RUNNING_TESTS.md b/tests/RUNNING_TESTS.md
index 23c74f4411..d9306d78d7 100644
--- a/tests/RUNNING_TESTS.md
+++ b/tests/RUNNING_TESTS.md
@@ -110,12 +110,16 @@ Slow tests
 --------------
 
 Certain tests, such as the UTF-8 normalizer or the DNS tests tend to be slow.
-Thus these tests are in the `slow` group, which is excluded by default. You can
-enable slow tests by copying the phpunit.xml.all file to phpunit.xml. If you
+Thus these tests are in the `slow` group, which is excluded by default. If you
 only want the slow tests, run:
 
     $ phpBB/vendor/bin/phpunit --group slow
 
+If you want all tests, run:
+
+    $ phpBB/vendor/bin/phpunit --group __nogroup__,functional,slow
+
+
 Functional tests
 -----------------
 
@@ -136,10 +140,10 @@ on which to run tests.
 
     $phpbb_functional_url = 'http://localhost/phpBB3/';
 
-To then run the tests, you run PHPUnit, but use the phpunit.xml.functional
-config file instead of the default one. Specify this through the "-c" option:
+Functional tests are automatically run, if '$phpbb_functional_url' is configured.
+If you only want the functional tests, run:
 
-    $ phpBB/vendor/bin/phpunit -c phpunit.xml.functional
+    $ phpBB/vendor/bin/phpunit --group functional
 
 This will change your board's config.php file, but it makes a backup at
 config_dev.php, so you can restore it after the test run is complete.