diff --git a/Lib/os.py b/Lib/os.py
index 14dc908827f..d974c59fa0f 100644
--- a/Lib/os.py
+++ b/Lib/os.py
@@ -40,6 +40,10 @@
 			exec 'from %s import _exit' % name
 		except ImportError:
 			pass
+		try:
+			environ
+		except:
+			environ = {} # Make sure os.environ exists, at least
 		break
 else:
 	del name