diff --git a/fedireads/forms.py b/fedireads/forms.py
index 75bc56ab2..dc59a8a9e 100644
--- a/fedireads/forms.py
+++ b/fedireads/forms.py
@@ -54,3 +54,9 @@ class EditUserForm(ModelForm):
         fields = ['avatar', 'name', 'summary']
         help_texts = {f: None for f in fields}
 
+class TagForm(ModelForm):
+    class Meta:
+        model = models.Tag
+        fields = ['name']
+        help_texts = {f: None for f in fields}
+
diff --git a/fedireads/models/activity.py b/fedireads/models/activity.py
index 58789dc58..93e70313a 100644
--- a/fedireads/models/activity.py
+++ b/fedireads/models/activity.py
@@ -47,6 +47,13 @@ class Review(Status):
         super().save(*args, **kwargs)
 
 
+class Tag(FedireadsModel):
+    ''' freeform tags for books '''
+    users = models.ManyToManyField('User')
+    books = models.ManyToManyField('Book')
+    name = models.CharField(max_length=140, unique=True)
+
+
 class Favorite(FedireadsModel):
     ''' fav'ing a post '''
     user = models.ForeignKey('User', on_delete=models.PROTECT)
diff --git a/fedireads/outgoing.py b/fedireads/outgoing.py
index a87cc6f3b..e75e75767 100644
--- a/fedireads/outgoing.py
+++ b/fedireads/outgoing.py
@@ -7,7 +7,7 @@ from urllib.parse import urlencode
 
 from fedireads import activitypub
 from fedireads import models
-from fedireads.status import create_review, create_status
+from fedireads.status import create_review, create_status, create_tag
 from fedireads.remote_user import get_or_create_remote_user
 from fedireads.broadcast import get_recipients, broadcast
 
@@ -160,6 +160,11 @@ def handle_review(user, book, name, content, rating):
     other_recipients = get_recipients(user, 'public', limit='other')
     broadcast(user, article_create_activity, other_recipients)
 
+def handle_tag(user, book, name):
+    tag = create_tag(user, book, name)
+
+    tag_activity = activitypub.get_tag(tag)
+    book_object = activitypub.get_book(book)
 
 def handle_comment(user, review, content):
     ''' respond to a review or status '''
diff --git a/fedireads/status.py b/fedireads/status.py
index 2114e94d7..190167e9b 100644
--- a/fedireads/status.py
+++ b/fedireads/status.py
@@ -45,6 +45,21 @@ def create_status(user, content, reply_parent=None, mention_books=None):
     return status
 
 
+def create_tag(user, possible_book, name):
+    ''' add a tag to a book '''
+    book = get_or_create_book(possible_book)
+
+    try:
+        # check for an existing tag with this text
+        tag = models.Tag.objects.get(name=name)
+    except models.Tag.DoesNotExist():
+        # create a new one if there isn't an existing one
+        tag = models.Tag.objects.create(name=name)
+    tag.users.add(user)
+    tag.books.add(book)
+    return tag
+
+
 def sanitize(content):
     ''' remove invalid html from free text '''
     parser = InputHtmlParser()
diff --git a/fedireads/templates/book.html b/fedireads/templates/book.html
index 624a3bb58..b62929453 100644
--- a/fedireads/templates/book.html
+++ b/fedireads/templates/book.html
@@ -12,6 +12,12 @@
         {% if not reviews %}
         <p>No reviews yet!</p>
         {% endif %}
+        <form class="tag-form" name="tag" action="/tag/" method="post">
+            {% csrf_token %}
+            <input type="hidden" name="book" value="{{ book.openlibrary_key }}"></input>
+            {{ tag_form.as_p }}
+            <button type="submit">Add tag</button>
+        </form>
         <form class="review-form" name="review" action="/review/" method="post">
             {% csrf_token %}
             <input type="hidden" name="book" value="{{ book.openlibrary_key }}"></input>
diff --git a/fedireads/urls.py b/fedireads/urls.py
index a2bbaf8f2..fb694461b 100644
--- a/fedireads/urls.py
+++ b/fedireads/urls.py
@@ -51,6 +51,7 @@ urlpatterns = [
 
     # internal action endpoints
     re_path(r'^review/?$', views.review),
+    re_path(r'^tag/?$', views.tag),
     re_path(r'^comment/?$', views.comment),
     re_path(r'^favorite/(?P<status_id>\d+)/?$', views.favorite),
     re_path(
diff --git a/fedireads/utils/models.py b/fedireads/utils/models.py
index 10a86aaff..f7cb8e955 100644
--- a/fedireads/utils/models.py
+++ b/fedireads/utils/models.py
@@ -11,7 +11,7 @@ class FedireadsModel(models.Model):
     def absolute_id(self):
         ''' constructs the absolute reference to any db object '''
         base_path = 'https://%s' % DOMAIN
-        if self.user:
+        if hasattr(self, 'user'):
             base_path = self.user.absolute_id
         model_name = type(self).__name__.lower()
         return '%s/%s/%d' % (base_path, model_name, self.id)
diff --git a/fedireads/views.py b/fedireads/views.py
index e8af812e5..d0a8161c4 100644
--- a/fedireads/views.py
+++ b/fedireads/views.py
@@ -50,7 +50,8 @@ def home_tab(request, tab):
     if tab == 'home':
         # people you follow and direct mentions
         activities = activities.filter(
-            Q(user__in=following, privacy='public') | Q(mention_users=request.user)
+            Q(user__in=following, privacy='public') | \
+                Q(mention_users=request.user)
         )
     elif tab == 'local':
         # everyone on this instance
@@ -272,6 +273,19 @@ def review(request):
     return redirect('/book/%s' % book_identifier)
 
 
+@login_required
+def tag(request):
+    ''' tag a book '''
+    form = forms.ReviewForm(request.POST)
+    book_identifier = request.POST.get('book')
+    if not form.is_valid():
+        return redirect('/book/%s' % book_identifier)
+
+    name = form.data.get('name')
+    outgoing.handle_tag(request.user, book_identifier, name)
+    return redirect('/book/%s' % book_identifier)
+
+
 @login_required
 def comment(request):
     ''' respond to a book review '''