diff --git a/plumbum/cli/application.py b/plumbum/cli/application.py
index 9d0677125..04e8e0ab3 100644
--- a/plumbum/cli/application.py
+++ b/plumbum/cli/application.py
@@ -11,6 +11,8 @@
 
 class ShowHelp(SwitchError):
     pass
+class ShowHelpAll(SwitchError):
+    pass
 class ShowVersion(SwitchError):
     pass
 
@@ -274,6 +276,8 @@ def _parse_args(self, argv):
     def _validate_args(self, swfuncs, tailargs):
         if six.get_method_function(self.help) in swfuncs:
             raise ShowHelp()
+        if six.get_method_function(self.helpall) in swfuncs:
+            raise ShowHelpAll()
         if six.get_method_function(self.version) in swfuncs:
             raise ShowVersion()
 
@@ -334,6 +338,8 @@ def run(cls, argv = sys.argv, exit = True):  # @ReservedAssignment
             ordered, tailargs = inst._validate_args(swfuncs, tailargs)
         except ShowHelp:
             inst.help()
+        except ShowHelpAll:
+            inst.helpall()
         except ShowVersion:
             inst.version()
         except SwitchError:
@@ -384,6 +390,21 @@ def cleanup(self, retcode):
         :param retcode: the return code of ``main()``
         """
 
+    @switch(["--help-all"], overridable = True, group = "Meta-switches")
+    def helpall(self):
+        """Print help messages of all subcommands and quit"""
+        self.help()
+        print("")
+
+        if self._subcommands:
+            for name, subcls in sorted(self._subcommands.items()):
+                subapp = (subcls.get())("%s %s" % (self.PROGNAME, name))
+                subapp.parent = self
+                for si in subapp._switches_by_func.values():
+                    if si.group == "Meta-switches":
+                        si.group = "Hidden-switches"
+                subapp.helpall()
+
     @switch(["-h", "--help"], overridable = True, group = "Meta-switches")
     def help(self):  # @ReservedAssignment
         """Prints this help message and quits"""