diff --git a/Doc/library/multiprocessing.rst b/Doc/library/multiprocessing.rst
index 1d0920a..a778159 100644
--- a/Doc/library/multiprocessing.rst
+++ b/Doc/library/multiprocessing.rst
@@ -186,6 +186,13 @@
 use :func:`get_context` to avoid interfering with the choice of the
 library user.
 
+.. warning::
+
+   The ``'spawn'`` and ``'forkserver'`` start methods cannot currently
+   be used with "frozen" executables (i.e., binaries produced by
+   packages like **PyInstaller** and **cx_Freeze**) on Unix.
+   The ``'fork'`` start method does work.
+
 
 Exchanging objects between processes
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~