diff --git a/tclCommands/TclCommandListSys.py b/tclCommands/TclCommandListSys.py
new file mode 100644
index 00000000..87d5a761
--- /dev/null
+++ b/tclCommands/TclCommandListSys.py
@@ -0,0 +1,56 @@
+from tclCommands.TclCommand import *
+
+
+class TclCommandListSys(TclCommand):
+    """
+    Tcl shell command to get the list of system variables
+
+    example:
+        list_sys
+    """
+
+    # List of all command aliases, to be able use old names for backward compatibility (add_poly, add_polygon)
+    aliases = ['list_sys', 'listsys']
+
+    # Dictionary of types from Tcl command, needs to be ordered
+    arg_names = collections.OrderedDict([
+        ('selection', str),
+    ])
+
+    # Dictionary of types from Tcl command, needs to be ordered , this  is  for options  like -optionname value
+    option_types = collections.OrderedDict([
+
+    ])
+
+    # array of mandatory options for current Tcl command: required = {'name','outname'}
+    required = []
+
+    # structured help for current command, args needs to be ordered
+    help = {
+        'main': "Returns the list of the names of system variables.\n"
+                "Without an argument it will list all the system parameters. "
+                "As an argument use first letter or first letters from the name "
+                "of the system variable.\n"
+                "In that case it will list only the system variables that starts with that string.\n"
+                "Main categories start with: gerber or excellon or geometry or cncjob or global.\n"
+                "Note: Use get_sys TclCommand to get the value and set_sys TclCommand to set it.\n",
+        'args': collections.OrderedDict([
+        ]),
+        'examples': ['list_sys',
+                     'list_sys ser'
+                     'list_sys gerber',
+                     'list_sys cncj']
+    }
+
+    def execute(self, args, unnamed_args):
+        """
+
+        :param args:
+        :param unnamed_args:
+        :return:
+        """
+        if 'selection' in args:
+            argument = args['selection']
+            return str([k for k in self.app.defaults.keys() if str(k).startswith(str(argument))])
+        else:
+            return str([*self.app.defaults])
\ No newline at end of file
diff --git a/tclCommands/__init__.py b/tclCommands/__init__.py
index c1ffc809..bb646c84 100644
--- a/tclCommands/__init__.py
+++ b/tclCommands/__init__.py
@@ -26,6 +26,7 @@ import tclCommands.TclCommandInteriors
 import tclCommands.TclCommandIsolate
 import tclCommands.TclCommandJoinExcellon
 import tclCommands.TclCommandJoinGeometry
+import tclCommands.TclCommandListSys
 import tclCommands.TclCommandMillHoles
 import tclCommands.TclCommandMirror
 import tclCommands.TclCommandNew