diff --git a/pathvalidate/_filename.py b/pathvalidate/_filename.py
index d5c8f53..1e9655e 100644
--- a/pathvalidate/_filename.py
+++ b/pathvalidate/_filename.py
@@ -78,6 +78,8 @@ def sanitize(self, value: PathType, replacement_text: str = "") -> PathType:
                 if self.platform in [Platform.UNIVERSAL, Platform.WINDOWS]:
                     # Do not end a file or directory name with a space or a period
                     sanitized_filename = sanitized_filename.rstrip(" .")
+                    # Do not start a file or directory name with a space
+                    sanitized_filename = sanitized_filename.lstrip(" ")
             elif e.reason == ErrorReason.NULL_NAME:
                 return self._null_value_handler(e)
             else:
@@ -209,6 +211,15 @@ def __validate_win_filename(self, unicode_filename: str) -> None:
                 description="Do not end a file or directory name with a space or a period",
             )
 
+        if unicode_filename[0] in (" "):
+            raise InvalidCharError(
+                self._ERROR_MSG_TEMPLATE.format(
+                    invalid=re.escape(unicode_filename[0]), value=repr(unicode_filename)
+                ),
+                platform=Platform.WINDOWS,
+                description="Do not start a file or directory name with a space",
+            )
+
 
 def validate_filename(
     filename: PathType,
diff --git a/test/test_filename.py b/test/test_filename.py
index cbdbdca..152acd9 100644
--- a/test/test_filename.py
+++ b/test/test_filename.py
@@ -541,8 +541,11 @@ def test_normal_check_reserved(self, value, check_reserved, expected):
         [
             ["windows", "period.", "period"],
             ["windows", "space ", "space"],
+            ["windows", " space ", "space"],
             ["windows", "space_and_period .", "space_and_period"],
             ["windows", "space_and_period. ", "space_and_period"],
+            ["windows", " .space_and_period", ".space_and_period"],
+            ["windows", ". space_and_period", ". space_and_period"],
             ["linux", "period.", "period."],
             ["linux", "space ", "space "],
             ["linux", "space_and_period. ", "space_and_period. "],