diff --git a/tests/test_33_identifier.py b/tests/test_33_identifier.py
new file mode 100644
index 0000000..9f2b292
--- /dev/null
+++ b/tests/test_33_identifier.py
@@ -0,0 +1,143 @@
+#!/usr/bin/env python
+
+from saml2 import samlp
+from saml2.saml import NAMEID_FORMAT_PERSISTENT, NAMEID_FORMAT_TRANSIENT
+from saml2.config import Config
+from saml2.server import Identifier
+from saml2.assertion import Policy
+
+
+def _eq(l1,l2):
+    return set(l1) == set(l2)
+
+CONFIG = Config().load({
+    "entityid" :  "urn:mace:example.com:idp:2",
+    "service": {
+        "idp": {
+            "url" : "http://idp.example.org/",
+            "name" : "test",
+            "assertions": {
+                "default": {
+                    "lifetime": {"minutes":15},
+                    "attribute_restrictions": None, # means all I have
+                    "name_form": "urn:oasis:names:tc:SAML:2.0:attrname-format:uri",
+                    "nameid_format": NAMEID_FORMAT_PERSISTENT
+                },
+            }
+        }
+    },
+    "xmlsec_binary" : "/usr/local/bin/xmlsec1",
+    "virtual_organization" : {
+        "http://vo.example.org/biomed":{
+            "nameid_format" : "urn:oid:2.16.756.1.2.5.1.1.1-NameID",
+            "common_identifier": "uid",
+        },
+        "http://vo.example.org/design":{
+        }
+    }
+})
+
+NAME_ID_POLICY_1 = """<?xml version="1.0" encoding="utf-8"?>
+<NameIDPolicy xmlns="urn:oasis:names:tc:SAML:2.0:protocol"
+  SPNameQualifier="http://vo.example.org/biomed"
+/>
+"""
+
+NAME_ID_POLICY_2 = """<?xml version="1.0" encoding="utf-8"?>
+<NameIDPolicy xmlns="urn:oasis:names:tc:SAML:2.0:protocol"
+  SPNameQualifier="http://vo.example.org/design"
+/>
+"""
+
+
+class TestIdentifier():
+    def setup_class(self):
+        self.id = Identifier("subject.db", CONFIG["entityid"], 
+                            CONFIG.vo_conf)
+        
+    def test_persistent_1(self):
+        policy = Policy({
+            "default": {
+                "name_form": "urn:oasis:names:tc:SAML:2.0:attrname-format:uri",
+                "nameid_format": NAMEID_FORMAT_PERSISTENT,
+                "attribute_restrictions": {
+                    "surName": [".*berg"],
+                }
+            }
+        })
+        
+        nameid = self.id.construct_nameid(policy, "foobar", 
+                                            "urn:mace:example.com:sp:1")
+        
+        assert _eq(nameid.keys(), ['text', 'sp_name_qualifier', 'format'])
+        assert nameid["sp_name_qualifier"] == CONFIG["entityid"]
+        assert nameid["format"] == NAMEID_FORMAT_PERSISTENT
+        
+        nameid_2 = self.id.construct_nameid(policy, "foobar", 
+                                            "urn:mace:example.com:sp:1")
+        
+        assert nameid == nameid_2
+        assert nameid["text"] == nameid_2["text"]
+        
+    def test_transient_1(self):
+        policy = Policy({
+            "default": {
+                "name_form": "urn:oasis:names:tc:SAML:2.0:attrname-format:uri",
+                "nameid_format": NAMEID_FORMAT_TRANSIENT,
+                "attribute_restrictions": {
+                    "surName": [".*berg"],
+                }
+            }
+        })
+        nameid = self.id.construct_nameid(policy, "foobar", 
+                                            "urn:mace:example.com:sp:1")
+        
+        assert _eq(nameid.keys(), ['text', 'format'])
+        assert nameid["format"] == NAMEID_FORMAT_TRANSIENT
+        
+    def test_vo_1(self):
+        policy = Policy({
+            "default": {
+                "name_form": "urn:oasis:names:tc:SAML:2.0:attrname-format:uri",
+                "nameid_format": NAMEID_FORMAT_PERSISTENT,
+                "attribute_restrictions": {
+                    "surName": [".*berg"],
+                }
+            }
+        })
+        
+        name_id_policy = samlp.name_id_policy_from_string(NAME_ID_POLICY_1)
+        nameid = self.id.construct_nameid(policy, "foobar", 
+                                            "urn:mace:example.com:sp:1", 
+                                            {"uid": "foobar01"},
+                                            name_id_policy)
+        
+        assert _eq(nameid.keys(), ['text', 'sp_name_qualifier', 'format'])
+        assert nameid["sp_name_qualifier"] == 'http://vo.example.org/biomed'
+        assert nameid["format"] == \
+                CONFIG.vo_conf('http://vo.example.org/biomed')["nameid_format"]
+        assert nameid["text"] == "foobar01"
+
+    def test_vo_2(self):
+        policy = Policy({
+            "default": {
+                "name_form": "urn:oasis:names:tc:SAML:2.0:attrname-format:uri",
+                "nameid_format": NAMEID_FORMAT_PERSISTENT,
+                "attribute_restrictions": {
+                    "surName": [".*berg"],
+                }
+            }
+        })
+        
+        name_id_policy = samlp.name_id_policy_from_string(NAME_ID_POLICY_2)
+        
+        nameid = self.id.construct_nameid(policy, "foobar", 
+                                            "urn:mace:example.com:sp:1", 
+                                            {"uid": "foobar01"},
+                                            name_id_policy)
+        
+        assert _eq(nameid.keys(), ['text', 'sp_name_qualifier', 'format'])
+        assert nameid["sp_name_qualifier"] == 'http://vo.example.org/design'
+        assert nameid["format"] == NAMEID_FORMAT_PERSISTENT
+        assert nameid["text"] != "foobar01"
+