diff --git a/emacs.d/00-functions.el b/emacs.d/00-functions.el
index 2b43d65..ff493f0 100644
--- a/emacs.d/00-functions.el
+++ b/emacs.d/00-functions.el
@@ -26,3 +26,11 @@
                          '(2 "_NET_WM_STATE_MAXIMIZED_VERT" 0))
   (x-send-client-message nil 0 nil "_NET_WM_STATE" 32
                          '(2 "_NET_WM_STATE_MAXIMIZED_HORZ" 0)))
+
+(defun c-toggle-header-source ()
+  (interactive)
+  (let ((ext (file-name-extension (buffer-file-name)))
+        (noext (file-name-sans-extension (buffer-file-name))))
+    (if (string= (substring ext 0 1) "c")
+        (find-file (concat noext ".h"))
+      (find-file (concat noext ".c")))))
diff --git a/emacs.d/20-c-mode.el b/emacs.d/20-c-mode.el
new file mode 100644
index 0000000..2b05b94
--- /dev/null
+++ b/emacs.d/20-c-mode.el
@@ -0,0 +1,3 @@
+(add-hook 'c-mode-hook
+          (lambda ()
+            (local-set-key [f11] 'c-toggle-header-source)))