diff --git a/docs/advanced.rst b/docs/advanced.rst
index e595be5e..c0fefa6c 100644
--- a/docs/advanced.rst
+++ b/docs/advanced.rst
@@ -293,6 +293,10 @@ will detect it.
     - ``PIPENV_IGNORE_VIRTUALENVS`` — Set to disable automatically using an activated virtualenv over
       the current project's own virtual environment.
 
+    - ``PIPENV_PIPFILE`` — When running pipenv from a $PWD other than the same
+      directory where the Pipfile is located, instruct pipenv to find the
+      Pipfile in the location specified by this environment variable.
+
 If you'd like to set these environment variables on a per-project basis, I recommend utilizing the fantastic `direnv <https://direnv.net>`_ project, in order to do so.
 
 Also note that `pip itself supports environment variables <https://pip.pypa.io/en/stable/user_guide/#environment-variables>`_, if you need additional customization.