diff --git a/src/xmpp_api/exceptions/base.py b/src/xmpp_api/exceptions/base.py
index fbebae8..7083dc8 100644
--- a/src/xmpp_api/exceptions/base.py
+++ b/src/xmpp_api/exceptions/base.py
@@ -6,3 +6,13 @@ class ConfigurationException(Exception):
 
     def __init__(self, msg: str):
         super().__init__(msg)
+
+
+class UnknownConstraintException(Exception):
+    """
+    Exception that is raised when there is a constraint type
+    that we do not know about.
+    """
+
+    def __init__(self, msg: str):
+        super().__init__(msg)
diff --git a/src/xmpp_api/util/constraints.py b/src/xmpp_api/util/constraints.py
index 093ae08..010289c 100644
--- a/src/xmpp_api/util/constraints.py
+++ b/src/xmpp_api/util/constraints.py
@@ -1,5 +1,6 @@
 import xmpp_api.api.types.v1.bot as bot_api
 import xmpp_api.db.bot as bot_db
+from xmpp_api.exceptions.base import UnknownConstraintException
 
 
 def bot_constraint_to_db(constraint: bot_api.BotConstraint) -> bot_db.BotConstraint:
@@ -9,8 +10,7 @@ def bot_constraint_to_db(constraint: bot_api.BotConstraint) -> bot_db.BotConstra
                 domains=constraint.domains,
             )
         case _:
-            # TODO: Proper exception type
-            raise Exception()
+            raise UnknownConstraintException(constraint.__class__.__name__)
 
 
 def bot_constraint_from_db(constraint: bot_db.BotConstraint) -> bot_api.BotConstraint:
@@ -20,5 +20,4 @@ def bot_constraint_from_db(constraint: bot_db.BotConstraint) -> bot_api.BotConst
                 domains=constraint.domains,
             )
         case _:
-            # TODO: Proper exception type
-            raise Exception()
+            raise UnknownConstraintException(constraint.__class__.__name__)