diff --git a/greg/migrations/0001_initial.py b/greg/migrations/0001_initial.py
index 4d782f4e1539199a6e98a9b67e8dacf118aad24d..2c80ebc6d2ad8a030b9b27027d8f2ac1d0126249 100644
--- a/greg/migrations/0001_initial.py
+++ b/greg/migrations/0001_initial.py
@@ -1,4 +1,4 @@
-# Generated by Django 3.2.5 on 2021-07-13 06:47
+# Generated by Django 3.2.5 on 2021-07-13 13:44
 
 import datetime
 import dirtyfields.dirtyfields
@@ -200,7 +200,7 @@ class Migration(migrations.Migration):
         ),
         migrations.AddConstraint(
             model_name='personrole',
-            constraint=models.UniqueConstraint(fields=('person', 'role'), name='personrole_person_role_unique'),
+            constraint=models.UniqueConstraint(fields=('person', 'role', 'unit'), name='personrole_person_role_unit_unique'),
         ),
         migrations.AddConstraint(
             model_name='personconsent',
diff --git a/greg/models.py b/greg/models.py
index 9e3a030443cd60a9471204eba7928a979fe44945..84403c8ba2e7735a05a2b6dc490459a0cc2d165c 100644
--- a/greg/models.py
+++ b/greg/models.py
@@ -106,7 +106,7 @@ class PersonRole(BaseModel):
     class Meta:
         constraints = [
             models.UniqueConstraint(
-                fields=["person", "role"], name="personrole_person_role_unique"
+                fields=["person", "role", "unit"], name="personrole_person_role_unit_unique"
             )
         ]