diff --git a/nml/grfstrings.py b/nml/grfstrings.py
index b94c04a2..17e41a05 100644
--- a/nml/grfstrings.py
+++ b/nml/grfstrings.py
@@ -825,6 +825,8 @@ class Language:
     @type strings: C{dict} of
     """
 
+    used_strings = []
+
     def __init__(self, default):
         self.default = default
         self.langid = None
@@ -985,6 +987,9 @@ def get_string(self, string, lang_id):
         assert string_id in self.strings
         assert lang_id == self.langid or self.langid == DEFAULT_LANGUAGE
 
+        if string_id not in Language.used_strings:
+            Language.used_strings.append(string_id)
+
         str_type = self.strings[string_id].get_type()
         parsed_string = ""
         if self.strings[string_id].gender is not None:
@@ -1291,3 +1296,10 @@ def read_lang_files(lang_dir, default_lang_file):
             continue
         parse_file(filename, False)
     langs.sort()
+
+
+def list_unused_strings():
+    for string in default_lang.strings:
+        if string in Language.used_strings:
+            continue
+        generic.print_warning(generic.Warning.GENERIC, 'String "{}" is unused'.format(string))
diff --git a/nml/main.py b/nml/main.py
index 393d46cf..0bd13294 100644
--- a/nml/main.py
+++ b/nml/main.py
@@ -90,6 +90,7 @@ def parse_cli(argv):
         allow_extra_zoom=True,
         allow_32bpp=True,
         disable_palette_validation=False,
+        list_unused_strings=False,
     )
     opt_parser.add_option("-d", "--debug", action="store_true", dest="debug", help="write the AST to stdout")
     opt_parser.add_option("-s", "--stack", action="store_true", dest="stack", help="Dump stack when an error occurs")
@@ -231,6 +232,9 @@ def parse_cli(argv):
         dest="disable_palette_validation",
         help="Disable palette validation for sprites",
     )
+    opt_parser.add_option(
+        "--list-unused-strings", action="store_true", dest="list_unused_strings", help="List unused strings"
+    )
 
     opts, args = opt_parser.parse_args(argv)
 
@@ -359,6 +363,9 @@ def main(argv):
     )
 
     input.close()
+
+    if opts.list_unused_strings:
+        grfstrings.list_unused_strings()
     sys.exit(ret)