diff --git a/src/iam/models.py b/src/iam/models.py
index 5e9b821..1387cca 100644
--- a/src/iam/models.py
+++ b/src/iam/models.py
@@ -42,7 +42,7 @@ class Permission(Base):
 		),
 	)
 
-	service_rel = relationship("Service", foreign_keys=[service_id])
+	service_rel = relationship("Service", foreign_keys="Permission.service_id")
 
 	@property
 	def service_name(self):
diff --git a/src/organisation/models.py b/src/organisation/models.py
index e99d64f..5879ab6 100644
--- a/src/organisation/models.py
+++ b/src/organisation/models.py
@@ -39,15 +39,21 @@ class Organisation(Base):
 	)
 
 	group_rel = relationship("Group", back_populates="org_rel")
-	root_user_rel = relationship("User", foreign_keys=[root_user_id])
+	root_user_rel = relationship("User", foreign_keys="Organisation.root_user_id")
 
 	@property
 	def root_user_email(self):
 		return self.root_user_rel.email if self.root_user_rel else None
 
-	billing_contact_rel = relationship("Contact", foreign_keys=[billing_contact_id])
-	security_contact_rel = relationship("Contact", foreign_keys=[security_contact_id])
-	owner_contact_rel = relationship("Contact", foreign_keys=[owner_contact_id])
+	billing_contact_rel = relationship(
+		"Contact", foreign_keys="Organisation.billing_contact_id"
+	)
+	security_contact_rel = relationship(
+		"Contact", foreign_keys="Organisation.security_contact_id"
+	)
+	owner_contact_rel = relationship(
+		"Contact", foreign_keys="Organisation.owner_contact_id"
+	)
 
 
 class OrgUsers(Base):