diff --git a/config.org b/config.org
index 69ce512..d0b4439 100644
--- a/config.org
+++ b/config.org
@@ -894,6 +894,19 @@ Preserve indentation in SRC blocks
 (setq org-src-preserve-indentation t)
 #+END_SRC
 
+** Org-todo
+
+When all children are done, automatically change the TODO parent entry to DONE.
+
+#+BEGIN_SRC emacs-lisp
+(defun org-summary-todo (n-done n-not-done)
+  "Switch entry to DONE when all subentries are done, to TODO otherwise."
+  (let (org-log-done org-todo-log-states)   ; turn off logging
+    (org-todo (if (= n-not-done 0) "DONE" "TODO"))))
+
+(add-hook 'org-after-todo-statistics-hook #'org-summary-todo)
+#+END_SRC
+
 ** Org bullets
 
 #+BEGIN_SRC emacs-lisp