diff --git a/docs/pages/reference/index.rst b/docs/pages/reference/index.rst
index 9a5cdff..6b11def 100644
--- a/docs/pages/reference/index.rst
+++ b/docs/pages/reference/index.rst
@@ -8,3 +8,4 @@ Reference
    function
    types
    handler
+   tips
diff --git a/docs/pages/reference/tips.rst b/docs/pages/reference/tips.rst
new file mode 100644
index 0000000..d51a246
--- /dev/null
+++ b/docs/pages/reference/tips.rst
@@ -0,0 +1,53 @@
+Tips
+------------
+
+Sanitize dot-files or dot-directories
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+When you process filenames or filepaths containing ``.`` or ``..`` with the ``sanitize_filename`` function or the ``sanitize_filepath`` function, by default, ``sanitize_filename`` does nothing, and ``sanitize_filepath`` normalizes the filepaths:
+
+.. code-block:: python
+
+    print(sanitize_filename("."))
+    print(sanitize_filepath("hoge/./foo"))
+
+.. code-block:: console
+
+    .
+    hoge/foo
+
+If you would like to replace ``.`` and ``..`` like other reserved words, you need to specify the arguments as follows:
+
+.. code-block:: python
+
+    from pathvalidate import sanitize_filepath, sanitize_filename
+    from pathvalidate.error import ValidationError
+
+
+    def always_add_trailing_underscore(e: ValidationError) -> str:
+        if e.reusable_name:
+            return e.reserved_name
+
+        return f"{e.reserved_name}_"
+
+
+    print(
+        sanitize_filename(
+            ".",
+            reserved_name_handler=always_add_trailing_underscore,
+            additional_reserved_names=[".", ".."],
+        )
+    )
+
+    print(
+        sanitize_filepath(
+            "hoge/./foo",
+            normalize=False,
+            reserved_name_handler=always_add_trailing_underscore,
+            additional_reserved_names=[".", ".."],
+        )
+    )
+
+.. code-block:: console
+
+    ._
+    hoge/._/foo