diff --git a/lib/spack/spack/cmd/share.py b/lib/spack/spack/cmd/share.py
new file mode 100644
index 00000000000..55c29a3d8ed
--- /dev/null
+++ b/lib/spack/spack/cmd/share.py
@@ -0,0 +1,82 @@
+# Copyright 2013-2019 Lawrence Livermore National Security, LLC and other
+# Spack Project Developers. See the top-level COPYRIGHT file for details.
+#
+# SPDX-License-Identifier: (Apache-2.0 OR MIT)
+
+import llnl.util.tty as tty
+
+import spack.cmd
+
+
+description = "enable shared mode for multi-user support"
+section = "share"
+level = "long"
+
+
+subcommands = [
+    'activate',
+    'deactivate',
+    'status'
+]
+
+subcommand_functions = {}
+
+
+def shr_activate_setup_parser(subparser):
+    pass
+
+
+def shr_deactivate_setup_parser(subparser):
+    pass
+
+
+def shr_status_setup_parser(subparser):
+    pass
+
+
+def shr_activate(args):
+    if spack.config.get('config:shared'):
+        tty.die("Shared mode already activated")
+    spack.config.set('config:shared', True, scope='site')
+
+
+def shr_deactivate(args):
+    if not spack.config.get('config:shared'):
+        tty.die("Shared mode already deactivated")
+    spack.config.set('config:shared', False, scope='site')
+
+
+def shr_status(args):
+    if spack.config.get('config:shared'):
+        tty.msg("Shared mode enabled")
+    else:
+        tty.msg("Shared mode disabled")
+
+
+def setup_parser(subparser):
+    sp = subparser.add_subparsers(metavar='SUBCOMMAND', dest='share_command')
+
+    for name in subcommands:
+        if isinstance(name, (list, tuple)):
+            name, aliases = name[0], name[1:]
+        else:
+            aliases = []
+
+        # add commands to subcommands dict
+        function_name = 'shr_%s' % name
+        function = globals()[function_name]
+        for alias in [name] + aliases:
+            subcommand_functions[alias] = function
+
+        # make a subparser and run the command's setup function on it
+        setup_parser_cmd_name = 'shr_%s_setup_parser' % name
+        setup_parser_cmd = globals()[setup_parser_cmd_name]
+
+        subsubparser = sp.add_parser(
+            name, aliases=aliases, help=setup_parser_cmd.__doc__)
+        setup_parser_cmd(subsubparser)
+
+
+def share(parser, args):
+    action = subcommand_functions[args.share_command]
+    action(args)