diff --git a/src/iam/models.py b/src/iam/models.py
index a06ff79..c9ccc51 100644
--- a/src/iam/models.py
+++ b/src/iam/models.py
@@ -42,7 +42,9 @@ class Permission(Base):
 		),
 	)
 
-	service_rel = relationship("Service", foreign_keys="Permission.service_id")
+	service_rel = relationship(
+		"Service", back_populates="permission_rel", foreign_keys="Permission.service_id"
+	)
 
 	@property
 	def service_name(self):
diff --git a/src/service/models.py b/src/service/models.py
index 82bdba1..414de5d 100644
--- a/src/service/models.py
+++ b/src/service/models.py
@@ -7,6 +7,7 @@ Models:
 """
 
 from sqlalchemy import Column, Integer, String
+from sqlalchemy.orm import relationship
 
 from src.database import Base
 
@@ -17,3 +18,5 @@ class Service(Base):
 	id = Column(Integer, primary_key=True)
 	name = Column(String, unique=True)
 	api_key = Column(String, unique=True)
+
+	permission_rel = relationship("Permission", back_populates="service_rel")