diff --git a/src/openflexure_microscope_server/things/__init__.py b/src/openflexure_microscope_server/things/__init__.py
index c497209f..838e649c 100644
--- a/src/openflexure_microscope_server/things/__init__.py
+++ b/src/openflexure_microscope_server/things/__init__.py
@@ -9,6 +9,10 @@ from typing import Optional, Self
 
 import labthings_fastapi as lt
 
+# To ensure consistency, we enable the feature flags we want here. This means
+# they will be enabled in any code that imports a `Thing` from this package.
+lt.FEATURE_FLAGS.validate_properties_on_set = True
+
 
 class OFMThing(lt.Thing):
     """A custom LabThings Thing class for the OpenFlexure Microscope."""