diff --git a/gwdatafind/ui.py b/gwdatafind/ui.py
index d95d2af16273c15d4b2c6bf101303ae9453cd3af..4752b89cb061ba3654869a06ee53bb6dc10d7d32 100644
--- a/gwdatafind/ui.py
+++ b/gwdatafind/ui.py
@@ -16,6 +16,13 @@
 # You should have received a copy of the GNU General Public License
 # along with GWDataFind.  If not, see <http://www.gnu.org/licenses/>.
 
+"""User interface functions for GWDataFind.
+
+These are all imported to the top-level namespace, so should be
+referred to in usage as ``gwdatafind.<function>`` and not
+``gwdatafind.ui.<function>``
+"""
+
 from functools import wraps
 from re import compile as compile_regex
 from urllib.parse import urlparse