diff --git a/docs/advanced.rst b/docs/advanced.rst
index 6ebb9f4d..4e18d08d 100644
--- a/docs/advanced.rst
+++ b/docs/advanced.rst
@@ -682,11 +682,9 @@ production environments for reproducible builds.
 ☤ Shell Completion
 ------------------
 
-Set ``_PIPENV_COMPLETE`` and then source the output of the program.
-For example, with ``fish``, put this in your
-``~/.config/fish/completions/pipenv.fish``::
+For fish:
 
-    eval (env _PIPENV_COMPLETE=source-fish pipenv)
+    eval (pipenv --completion)
 
 Magic shell completions are now enabled!
 
diff --git a/pipenv/cli.py b/pipenv/cli.py
index cc1308ce..17f208fb 100644
--- a/pipenv/cli.py
+++ b/pipenv/cli.py
@@ -1498,7 +1498,14 @@ def cli(
         sys.exit()
 
     if completion:
-        os.environ['_PIPENV_COMPLETE'] = 'source-{0}'.format(os.environ['SHELL'].split(os.sep)[-1])
+        try:
+            os.environ['_PIPENV_COMPLETE'] = 'source-{0}'.format(os.environ['SHELL'].split(os.sep)[-1])
+        except KeyError:
+            click.echo(
+                'Please ensure that the {0} environment variable '
+                'is set.'.format(crayons.white('SHELL', bold=True)), err=True)
+            sys.exit(1)
+
         c = delegator.run('pipenv')
         click.echo(c.out)
         sys.exit(0)