diff --git a/tests/test_message.py b/tests/test_message.py
index 220fef2..48004b1 100644
--- a/tests/test_message.py
+++ b/tests/test_message.py
@@ -1,5 +1,9 @@
+import pathlib
+import tempfile
+from typing import cast
 from .test_main import CmmTestCase
-from chatmastermind.message import source_code, MessageError, Question, Answer
+from chatmastermind.message import source_code, Message, MessageError, Question, Answer
+from chatmastermind.tags import Tag, TagLine
 
 
 class SourceCodeTestCase(CmmTestCase):
@@ -76,3 +80,213 @@ class AnswerTestCase(CmmTestCase):
         answer = Answer("No")
         self.assertIsInstance(answer, Answer)
         self.assertEqual(answer, "No")
+
+
+class MessageToFileTxtTestCase(CmmTestCase):
+    def setUp(self) -> None:
+        self.file = tempfile.NamedTemporaryFile(delete=False, suffix='.txt')
+        self.file_path = pathlib.Path(self.file.name)
+        self.message = Message(Question('This is a question.'),
+                               Answer('This is an answer.'),
+                               {Tag('tag1'), Tag('tag2')},
+                               self.file_path)
+
+    def tearDown(self) -> None:
+        self.file.close()
+        self.file_path.unlink()
+
+    def test_to_file_txt(self) -> None:
+        self.message.to_file(self.file_path)
+
+        with open(self.file_path, "r") as fd:
+            content = fd.read()
+        expected_content = f"""{TagLine.prefix} tag1 tag2
+{Question.txt_header}
+This is a question.
+{Answer.txt_header}
+This is an answer.
+"""
+        self.assertEqual(content, expected_content)
+
+    def test_to_file_unsupported_file_type(self) -> None:
+        unsupported_file_path = pathlib.Path("example.doc")
+        with self.assertRaises(MessageError) as cm:
+            self.message.to_file(unsupported_file_path)
+        self.assertEqual(str(cm.exception), "File type '.doc' is not supported")
+
+    def test_to_file_no_file_path(self) -> None:
+        """
+        Provoke an exception using an empty path.
+        """
+        with self.assertRaises(MessageError) as cm:
+            # clear the internal file_path
+            self.message.file_path = None
+            self.message.to_file(None)
+        self.assertEqual(str(cm.exception), "Got no valid path to write message")
+        # reset the internal file_path
+        self.message.file_path = self.file_path
+
+
+class MessageToFileYamlTestCase(CmmTestCase):
+    def setUp(self) -> None:
+        self.file = tempfile.NamedTemporaryFile(delete=False, suffix='.yaml')
+        self.file_path = pathlib.Path(self.file.name)
+        self.message = Message(Question('This is a question.'),
+                               Answer('This is an answer.'),
+                               {Tag('tag1'), Tag('tag2')},
+                               self.file_path)
+        self.message_multiline = Message(Question('This is a\nmultiline question.'),
+                                         Answer('This is a\nmultiline answer.'),
+                                         {Tag('tag1'), Tag('tag2')},
+                                         self.file_path)
+
+    def tearDown(self) -> None:
+        self.file.close()
+        self.file_path.unlink()
+
+    def test_to_file_yaml(self) -> None:
+        self.message.to_file(self.file_path)
+
+        with open(self.file_path, "r") as fd:
+            content = fd.read()
+        expected_content = "answer: This is an answer.\nquestion: This is a question.\ntags:\n- tag1\n- tag2\n"
+        self.assertEqual(content, expected_content)
+
+    def test_to_file_yaml_multiline(self) -> None:
+        self.message_multiline.to_file(self.file_path)
+
+        with open(self.file_path, "r") as fd:
+            content = fd.read()
+        expected_content = f"""{Answer.yaml_key}: |-
+  This is a
+  multiline answer.
+{Question.yaml_key}: |-
+  This is a
+  multiline question.
+{Message.tags_yaml_key}:
+- tag1
+- tag2
+"""
+        self.assertEqual(content, expected_content)
+
+
+class MessageFromFileTxtTestCase(CmmTestCase):
+    def setUp(self) -> None:
+        self.file = tempfile.NamedTemporaryFile(delete=False, suffix='.txt')
+        self.file_path = pathlib.Path(self.file.name)
+        with open(self.file_path, "w") as fd:
+            fd.write(f"""{TagLine.prefix} tag1 tag2
+{Question.txt_header}
+This is a question.
+{Answer.txt_header}
+This is an answer.
+""")
+        self.file_no_tags = tempfile.NamedTemporaryFile(delete=False, suffix='.txt')
+        self.file_path_no_tags = pathlib.Path(self.file_no_tags.name)
+        with open(self.file_path_no_tags, "w") as fd:
+            fd.write(f"""{Question.txt_header}
+This is a question.
+{Answer.txt_header}
+This is an answer.
+""")
+
+    def tearDown(self) -> None:
+        self.file.close()
+        self.file_no_tags.close()
+        self.file_path.unlink()
+        self.file_path_no_tags.unlink()
+
+    def test_from_file_txt(self) -> None:
+        message = Message.from_file(self.file_path)
+        self.assertIsNotNone(message)
+        self.assertIsInstance(message, Message)
+        if message:
+            self.assertEqual(message.question, 'This is a question.')
+            self.assertEqual(message.answer, 'This is an answer.')
+            self.assertSetEqual(cast(set[Tag], message.tags), {Tag('tag1'), Tag('tag2')})
+            self.assertEqual(message.file_path, self.file_path)
+
+    def test_from_file_txt_no_tags(self) -> None:
+        message = Message.from_file(self.file_path_no_tags)
+        self.assertIsNotNone(message)
+        self.assertIsInstance(message, Message)
+        if message:
+            self.assertEqual(message.question, 'This is a question.')
+            self.assertEqual(message.answer, 'This is an answer.')
+            self.assertSetEqual(cast(set[Tag], message.tags), set())
+            self.assertEqual(message.file_path, self.file_path_no_tags)
+
+    def test_from_file_txt_tags_match(self) -> None:
+        message = Message.from_file(self.file_path, tags_or={Tag('tag1')})
+        self.assertIsNotNone(message)
+        self.assertIsInstance(message, Message)
+        if message:
+            self.assertEqual(message.question, 'This is a question.')
+            self.assertEqual(message.answer, 'This is an answer.')
+            self.assertSetEqual(cast(set[Tag], message.tags), {Tag('tag1'), Tag('tag2')})
+            self.assertEqual(message.file_path, self.file_path)
+
+    def test_from_file_txt_tags_dont_match(self) -> None:
+        message = Message.from_file(self.file_path, tags_or={Tag('tag3')})
+        self.assertIsNone(message)
+
+    def test_from_file_not_exists(self) -> None:
+        file_not_exists = pathlib.Path("example.txt")
+        with self.assertRaises(MessageError) as cm:
+            Message.from_file(file_not_exists)
+        self.assertEqual(str(cm.exception), f"Message file '{file_not_exists}' does not exist")
+
+
+class MessageFromFileYamlTestCase(CmmTestCase):
+    def setUp(self) -> None:
+        self.file = tempfile.NamedTemporaryFile(delete=False, suffix='.yaml')
+        self.file_path = pathlib.Path(self.file.name)
+        with open(self.file_path, "w") as fd:
+            fd.write(f"""
+{Question.yaml_key}: |-
+  This is a question.
+{Answer.yaml_key}: |-
+  This is an answer.
+{Message.tags_yaml_key}:
+  - tag1
+  - tag2
+""")
+        self.file_no_tags = tempfile.NamedTemporaryFile(delete=False, suffix='.yaml')
+        self.file_path_no_tags = pathlib.Path(self.file_no_tags.name)
+        with open(self.file_path_no_tags, "w") as fd:
+            fd.write(f"""
+{Question.yaml_key}: |-
+  This is a question.
+{Answer.yaml_key}: |-
+  This is an answer.
+""")
+
+    def tearDown(self) -> None:
+        self.file.close()
+        self.file_path.unlink()
+
+    def test_from_file_yaml(self) -> None:
+        message = Message.from_file(self.file_path)
+        self.assertIsInstance(message, Message)
+        self.assertIsNotNone(message)
+        if message:
+            self.assertEqual(message.question, 'This is a question.')
+            self.assertEqual(message.answer, 'This is an answer.')
+            self.assertSetEqual(cast(set[Tag], message.tags), {Tag('tag1'), Tag('tag2')})
+            self.assertEqual(message.file_path, self.file_path)
+
+    def test_from_file_yaml_no_tags(self) -> None:
+        message = Message.from_file(self.file_path_no_tags)
+        self.assertIsInstance(message, Message)
+        self.assertIsNotNone(message)
+        if message:
+            self.assertEqual(message.question, 'This is a question.')
+            self.assertEqual(message.answer, 'This is an answer.')
+            self.assertSetEqual(cast(set[Tag], message.tags), set())
+            self.assertEqual(message.file_path, self.file_path_no_tags)
+
+    def test_from_file_not_exists(self) -> None:
+        file_not_exists = pathlib.Path("example.yaml")
+        with self.assertRaises(MessageError) as cm:
+            Message.from_file(file_not_exists)
+        self.assertEqual(str(cm.exception), f"Message file '{file_not_exists}' does not exist")