diff --git a/django/core/management.py b/django/core/management.py
index a4c572d939..4a16d214ec 100644
--- a/django/core/management.py
+++ b/django/core/management.py
@@ -494,6 +494,7 @@ class ModelErrorCollection:
 
 def validate():
     "Validates all installed models."
+    import django.models
     from django.core import meta
     e = ModelErrorCollection()
     module_list = meta.get_installed_model_modules()
@@ -544,6 +545,8 @@ def runserver(port):
         sys.exit(1)
     def inner_run():
         from django.conf.settings import SETTINGS_MODULE
+        print "Validating models..."
+        validate()
         print "\nStarting server on port %s with settings module %r." % (port, SETTINGS_MODULE)
         print "Go to http://127.0.0.1:%s/ for Django." % port
         print "Quit the server with CONTROL-C (Unix) or CTRL-BREAK (Windows)."
diff --git a/docs/django-admin.txt b/docs/django-admin.txt
index c5071f5335..bb734aaf1b 100644
--- a/docs/django-admin.txt
+++ b/docs/django-admin.txt
@@ -148,6 +148,12 @@ startproject [projectname]
 Creates a Django project directory structure for the given project name in the
 current directory.
 
+validate
+--------
+
+Validates all installed models (according to the ``INSTALLED_APPS`` setting)
+and prints validation errors to standard output.
+
 Available options
 =================