diff --git a/src/fastapi_toolsets/security/__init__.py b/src/fastapi_toolsets/security/__init__.py
index 2ff9c43..7e8b9de 100644
--- a/src/fastapi_toolsets/security/__init__.py
+++ b/src/fastapi_toolsets/security/__init__.py
@@ -1,14 +1,13 @@
 """Authentication helpers for FastAPI using Security()."""
 
-from .base import AuthSource
-from .multi import MultiAuth
-from .sources import BearerTokenAuth, CookieAuth, OAuth2Auth, OpenIDAuth
+from .abc import AuthSource
+from .sources import BearerTokenAuth, CookieAuth, MultiAuth, OAuth2Auth, OpenIDAuth
 
 __all__ = [
     "AuthSource",
     "BearerTokenAuth",
     "CookieAuth",
+    "MultiAuth",
     "OAuth2Auth",
     "OpenIDAuth",
-    "MultiAuth",
 ]
diff --git a/src/fastapi_toolsets/security/base.py b/src/fastapi_toolsets/security/abc.py
similarity index 100%
rename from src/fastapi_toolsets/security/base.py
rename to src/fastapi_toolsets/security/abc.py
diff --git a/src/fastapi_toolsets/security/sources/__init__.py b/src/fastapi_toolsets/security/sources/__init__.py
index 5fd948f..d716477 100644
--- a/src/fastapi_toolsets/security/sources/__init__.py
+++ b/src/fastapi_toolsets/security/sources/__init__.py
@@ -2,7 +2,8 @@
 
 from .bearer import BearerTokenAuth
 from .cookie import CookieAuth
+from .multi import MultiAuth
 from .oauth2 import OAuth2Auth
 from .openid import OpenIDAuth
 
-__all__ = ["BearerTokenAuth", "CookieAuth", "OAuth2Auth", "OpenIDAuth"]
+__all__ = ["BearerTokenAuth", "CookieAuth", "MultiAuth", "OAuth2Auth", "OpenIDAuth"]
diff --git a/src/fastapi_toolsets/security/sources/bearer.py b/src/fastapi_toolsets/security/sources/bearer.py
index c486e1c..3e49a33 100644
--- a/src/fastapi_toolsets/security/sources/bearer.py
+++ b/src/fastapi_toolsets/security/sources/bearer.py
@@ -9,7 +9,7 @@ from fastapi.security import HTTPAuthorizationCredentials, HTTPBearer, SecurityS
 
 from fastapi_toolsets.exceptions import UnauthorizedError
 
-from ..base import AuthSource, _call_validator
+from ..abc import AuthSource, _call_validator
 
 
 class BearerTokenAuth(AuthSource):
diff --git a/src/fastapi_toolsets/security/sources/cookie.py b/src/fastapi_toolsets/security/sources/cookie.py
index 573c58a..89eb2bf 100644
--- a/src/fastapi_toolsets/security/sources/cookie.py
+++ b/src/fastapi_toolsets/security/sources/cookie.py
@@ -13,7 +13,7 @@ from fastapi.security import APIKeyCookie, SecurityScopes
 
 from fastapi_toolsets.exceptions import UnauthorizedError
 
-from ..base import AuthSource, _call_validator
+from ..abc import AuthSource, _call_validator
 
 
 class CookieAuth(AuthSource):
diff --git a/src/fastapi_toolsets/security/multi.py b/src/fastapi_toolsets/security/sources/multi.py
similarity index 99%
rename from src/fastapi_toolsets/security/multi.py
rename to src/fastapi_toolsets/security/sources/multi.py
index 9420f40..00dc4c9 100644
--- a/src/fastapi_toolsets/security/multi.py
+++ b/src/fastapi_toolsets/security/sources/multi.py
@@ -8,7 +8,7 @@ from fastapi.security import SecurityScopes
 
 from fastapi_toolsets.exceptions import UnauthorizedError
 
-from .base import AuthSource
+from ..abc import AuthSource
 
 
 class MultiAuth:
diff --git a/src/fastapi_toolsets/security/sources/oauth2.py b/src/fastapi_toolsets/security/sources/oauth2.py
index 8759062..1cbff89 100644
--- a/src/fastapi_toolsets/security/sources/oauth2.py
+++ b/src/fastapi_toolsets/security/sources/oauth2.py
@@ -8,7 +8,7 @@ from fastapi.security import OAuth2PasswordBearer, SecurityScopes
 
 from fastapi_toolsets.exceptions import UnauthorizedError
 
-from ..base import AuthSource, _call_validator
+from ..abc import AuthSource, _call_validator
 
 
 class OAuth2Auth(AuthSource):
diff --git a/src/fastapi_toolsets/security/sources/openid.py b/src/fastapi_toolsets/security/sources/openid.py
index 9df66d7..f752ee5 100644
--- a/src/fastapi_toolsets/security/sources/openid.py
+++ b/src/fastapi_toolsets/security/sources/openid.py
@@ -8,7 +8,7 @@ from fastapi.security import OpenIdConnect, SecurityScopes
 
 from fastapi_toolsets.exceptions import UnauthorizedError
 
-from ..base import AuthSource, _call_validator
+from ..abc import AuthSource, _call_validator
 
 
 class OpenIDAuth(AuthSource):
diff --git a/tests/test_security.py b/tests/test_security.py
index 9ad13eb..206f11e 100644
--- a/tests/test_security.py
+++ b/tests/test_security.py
@@ -507,7 +507,7 @@ class TestMultiAuth:
         assert org_calls == ["org_acme"]
 
     def test_require_returns_new_multi_auth(self):
-        from fastapi_toolsets.security.multi import MultiAuth as MultiAuthClass
+        from fastapi_toolsets.security.sources import MultiAuth as MultiAuthClass
 
         bearer = BearerTokenAuth(role_validator)
         multi = MultiAuth(bearer)