diff --git a/CHANGES b/CHANGES
index 32f889a3..10ed8e9c 100644
--- a/CHANGES
+++ b/CHANGES
@@ -24,6 +24,7 @@ Codename to be decided, release date to be announced.
 - added support for per-package template and static-file directories.
 - removed support for `create_jinja_loader` which is no longer used
   in 0.5 due to the improved module support.
+- added a helper function to expose files from any directory.
 
 Version 0.4
 -----------
diff --git a/docs/api.rst b/docs/api.rst
index b6c81d10..d7f887e4 100644
--- a/docs/api.rst
+++ b/docs/api.rst
@@ -230,6 +230,8 @@ Useful Functions and Classes
 
 .. autofunction:: send_file
 
+.. autofunction:: send_from_directory
+
 .. autofunction:: escape
 
 .. autoclass:: Markup
diff --git a/flask/helpers.py b/flask/helpers.py
index 65506698..560492c6 100644
--- a/flask/helpers.py
+++ b/flask/helpers.py
@@ -303,6 +303,15 @@ def send_from_directory(directory, filename, **options):
             return send_from_directory(app.config['UPLOAD_FOLDER'],
                                        filename, as_attachment=True)
 
+    .. admonition:: Sending files and Performance
+
+       It is strongly recommended to activate either `X-Sendfile` support in
+       your webserver or (if no authentication happens) to tell the webserver
+       to serve files for the given path on its own without calling into the
+       web application for improved performance.
+
+    .. versionadded:: 0.5
+
     :param directory: the directory where all the files are stored.
     :param filename: the filename relative to that directory to
                      download.