diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index d90a63ad..348a6b5c 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -6,7 +6,7 @@ repos:
     exclude: (versioneer.py|_version.py)
     
 - repo: https://github.com/timothycrosley/isort
-  rev: 5.12.0
+  rev: 5.13.2
   hooks:
   - id: isort
 
diff --git a/rubicon_ml/domain/experiment.py b/rubicon_ml/domain/experiment.py
index d5118b37..e0dd4b38 100644
--- a/rubicon_ml/domain/experiment.py
+++ b/rubicon_ml/domain/experiment.py
@@ -4,12 +4,12 @@
 from datetime import datetime
 from typing import List, Optional
 
-from rubicon_ml.domain.mixin import TagMixin
+from rubicon_ml.domain.mixin import CommentMixin, TagMixin
 from rubicon_ml.domain.utils import TrainingMetadata, uuid
 
 
 @dataclass
-class Experiment(TagMixin):
+class Experiment(TagMixin, CommentMixin):
     project_name: str
 
     id: str = field(default_factory=uuid.uuid4)
@@ -20,4 +20,5 @@ class Experiment(TagMixin):
     commit_hash: Optional[str] = None
     training_metadata: Optional[TrainingMetadata] = None
     tags: List[str] = field(default_factory=list)
+    comments: List[str] = field(default_factory=list)
     created_at: datetime = field(default_factory=datetime.utcnow)
diff --git a/rubicon_ml/domain/mixin.py b/rubicon_ml/domain/mixin.py
index 974f3bdb..6485f50f 100644
--- a/rubicon_ml/domain/mixin.py
+++ b/rubicon_ml/domain/mixin.py
@@ -25,3 +25,18 @@ def remove_tags(self, tags: List[str]):
             A list of string tags to remove from this domain model.
         """
         self.tags = list(set(self.tags).difference(set(tags)))
+
+
+class CommentMixin:
+    """Adds comment support to a domain model."""
+
+    def add_comments(self, comments: List[str]):
+        """
+        Add new comments to this model.
+
+        Parameters
+        ----------
+        comments : List[str]
+            A list of string comments to add to the domain model.
+        """
+        self.comments.extend(comments)
diff --git a/rubicon_ml/repository/base.py b/rubicon_ml/repository/base.py
index 950cefd7..93b28303 100644
--- a/rubicon_ml/repository/base.py
+++ b/rubicon_ml/repository/base.py
@@ -1212,3 +1212,43 @@ def get_tags(self, project_name, experiment_id=None, entity_identifier=None, ent
         sorted_tag_data = [json.loads(tag_data[p]) for _, p in sorted_tag_paths]
 
         return sorted_tag_data
+
+    # ---------- Comments ----------
+
+    def _get_comment_metadata_root(
+        self, project_name, experiment_id=None, entity_identifier=None, entity_type=None
+    ):
+        """Returns the directory to write comments to."""
+        # comments and tags are currently written to the same root with a different filename
+        return self._get_tag_metadata_root(
+            project_name, experiment_id, entity_identifier, entity_type
+        )
+
+    def add_comments(
+        self, project_name, comments, experiment_id=None, entity_identifier=None, entity_type=None
+    ):
+        """Persist comments to the configured filesystem.
+
+        Parameters
+        ----------
+        project_name : str
+            The name of the project the object to comment
+            belongs to.
+        comments : list of str
+            The comment values to persist.
+        experiment_id : str, optional
+            The ID of the experiment to apply the comments
+            `comments` to.
+        entity_identifier : str, optional
+            The ID or name of the entity to apply the comments
+            `comments` to.
+        entity_type : str, optional
+            The name of the entity's type as returned by
+            `entity_cls.__class__.__name__`.
+        """
+        comment_metadata_root = self._get_comment_metadata_root(
+            project_name, experiment_id, entity_identifier, entity_type
+        )
+        comment_metadata_path = f"{comment_metadata_root}/comments_{domain.utils.uuid.uuid4()}.json"
+
+        self._persist_domain({"added_comments": comments}, comment_metadata_path)
diff --git a/tests/unit/domain/test_mixin.py b/tests/unit/domain/test_mixin.py
index 3d84792b..3b2ea6f1 100644
--- a/tests/unit/domain/test_mixin.py
+++ b/tests/unit/domain/test_mixin.py
@@ -1,9 +1,10 @@
-from rubicon_ml.domain.mixin import TagMixin
+from rubicon_ml.domain.mixin import CommentMixin, TagMixin
 
 
-class Taggable(TagMixin):
-    def __init__(self, tags=[]):
+class Taggable(TagMixin, CommentMixin):
+    def __init__(self, tags=[], comments=[]):
         self.tags = tags
+        self.comments = comments
 
 
 def test_add_tags():
@@ -25,3 +26,10 @@ def test_remove_tags():
     taggable.remove_tags(["x"])
 
     assert taggable.tags == ["y"]
+
+
+def test_add_comments():
+    taggable = Taggable()
+    taggable.add_comments(["x"])
+
+    assert taggable.comments == ["x"]
diff --git a/tests/unit/repository/test_base_repo.py b/tests/unit/repository/test_base_repo.py
index 4ceba57b..2405a0ae 100644
--- a/tests/unit/repository/test_base_repo.py
+++ b/tests/unit/repository/test_base_repo.py
@@ -980,3 +980,25 @@ def test_get_tags_with_no_results(memory_repository):
     )
 
     assert tags == []
+
+
+def test_add_comments(memory_repository):
+    repository = memory_repository
+    experiment = _create_experiment(repository)
+    repository.add_comments(
+        experiment.project_name,
+        ["this is a comment"],
+        experiment_id=experiment.id,
+        entity_type=experiment.__class__.__name__,
+    )
+
+    comments_glob = f"{repository.root_dir}/{slugify(experiment.project_name)}/experiments/{experiment.id}/comments_*.json"
+    comments_files = repository.filesystem.glob(comments_glob)
+
+    assert len(comments_files) == 1
+
+    open_file = repository.filesystem.open(comments_files[0])
+    with open_file as f:
+        comments_json = json.load(f)
+
+    assert ["this is a comment"] == comments_json["added_comments"]