diff --git a/pyramid_mailer/message.py b/pyramid_mailer/message.py
index 6428856..b24907f 100644
--- a/pyramid_mailer/message.py
+++ b/pyramid_mailer/message.py
@@ -139,6 +139,10 @@ def validate(self):
         if not (self.recipients or self.cc or self.bcc):
             raise InvalidMessage("No recipients have been added")
 
+        if (self.cc or self.bcc) and not self.recipients:
+            raise InvalidMessage("Must have at least one direct recipient "
+                                 "even if cc or bcc set")
+
         if not self.body and not self.html:
             raise InvalidMessage("No body has been set")