diff --git a/README.md b/README.md
index 07b9446..e226a31 100644
--- a/README.md
+++ b/README.md
@@ -247,8 +247,7 @@ EMAILADDRESS_OPTIONS = ['codeptid', 'copersonid', 'organizationid', 'orgidentity
 
 ### <a name="identifier"></a>[Identifier API](https://spaces.at.internet2.edu/display/COmanage/Identifier+API) (COmanage v3.3.0+)
 
-- `identifiers_add() -> dict`
-    - `### NOT IMPLEMENTED ###`
+- `identifiers_add(identity_type: str, identifier: str, login_flag: bool, person_type: str, person_id: int) -> dict`
     - Add a new Identifier.
 - `identifiers_assign() -> bool`
     - `### NOT IMPLEMENTED ###`
diff --git a/comanage_api/__init__.py b/comanage_api/__init__.py
index 39118f1..0f296f6 100644
--- a/comanage_api/__init__.py
+++ b/comanage_api/__init__.py
@@ -202,8 +202,8 @@ def email_addresses_view_one(self, email_address_id: int):
         return email_addresses_view_one(self, email_address_id=email_address_id)
 
     # Indentifier API
-    def identifiers_add(self):
-        return identifiers_add(self)
+    def identifiers_add(self, identity_type: str, identifier: str, login_flag: bool, person_type: str, person_id: int):
+        return identifiers_add(self, identity_type=identity_type, identifier=identifier, login_flag=login_flag, person_type=person_type, person_id=person_id)
 
     def identifiers_assign(self):
         return identifiers_assign(self)
diff --git a/comanage_api/_identifiers.py b/comanage_api/_identifiers.py
index 9b15692..d3e454b 100644
--- a/comanage_api/_identifiers.py
+++ b/comanage_api/_identifiers.py
@@ -5,8 +5,7 @@
 
 Methods
 -------
-identifiers_add() -> dict
-    ### NOT IMPLEMENTED ###
+identifiers_add(identity_type: str, identifier: str, login_flag: bool, person_type: str, person_id: int) -> dict
     Add a new Identifier.
 identifiers_assign() -> bool
     ### NOT IMPLEMENTED ###
@@ -28,18 +27,87 @@
 import json
 
 
-def identifiers_add(self) -> dict:
+def identifiers_add(self, identity_type: str, identifier: str, login_flag: bool, person_type: str, person_id: int) -> dict:
     """
-    ### NOT IMPLEMENTED ###
     Add a new Identifier.
 
-    :param self:
-    :return
-        501 Server Error: Not Implemented for url: mock://not_implemented_501.local:
+    identity_type: Identifier keyword (i.e. eppn, sorid)
+    identifier: The actual identifier for the indentity_type
+    login_flag: Whether this identifier is used for logging in
+    person_type: Type of person (i.e. "CO"|"Dept"|"Group"|"Org"|"Organization")
+    person_id: COmanage ID for the person_type
+    :request
+    {
+    "RequestType":"Identifiers",
+    "Version":"1.0",
+    "Identifiers":
+    [
+        {
+        "Version":"1.0",
+        "Type":"<Type>",
+        "Identifier":"<Identifier>",
+        "Login":true|false,
+        "Person":
+        {
+            "Type":("CO"|"Dept"|"Group"|"Org"|"Organization"),
+            "Id":"<ID>"
+        },
+        "CoProvisioningTargetId":"<CoProvisioningTargetId>",
+        "Status":"Active"|"Deleted"
+        }
+    ]
+    }:
+
+    Response Format
+        HTTP Status                  Response Body        Description
+        201  Added                   NewObjectResponse    Identifier added
+        400  Bad Request                                  Identifier Request not
+                                                            provided in POST body
+        400  Invalid Fields          ErrorResponse        An error in one or more
+                                                            provided fields
+        401  Unauthorized                                 Authentication required
+        403  Identifier In Use                            An entry already exists with the
+                                                            specified identifier
+        403  No Person Specified                          A CO Department, a CO Person, or an
+                                                            Org Identity must be specified to
+                                                            attach
+                                                            the Identifier to
+        403  Person Does Not Exist                        The specified CO Department,
+                                                            CO Person, or Org Identity
+                                                            does not exist
+        500  Other Error                                  Unknown error
     """
-    url = self._MOCK_501_URL
-    resp = self._mock_session.get(
-        url=url
+    post_body = {
+        "RequestType":"Identifiers",
+        "Version":"1.0",
+        "Identifiers":
+        [
+            {
+                "Version":"1.0",
+                "Type":"<Type>",
+                "Identifier":"<Identifier>",
+                "Login":"<Login>",
+                "Person":
+                {
+                    "Type":"<Type>",
+                    "Id":"<ID>"
+                },
+                "Status":"Active"
+            }
+        ]
+    }
+
+    post_body['Identifiers'][0]['Type'] = identity_type
+    post_body['Identifiers'][0]['Identifier'] = identifier
+    post_body['Identifiers'][0]['Login'] = login_flag
+    post_body['Identifiers'][0]['Person']['Type'] = person_type
+    post_body['Identifiers'][0]['Person']['Id'] = person_id
+
+    post_body = json.dumps(post_body)
+    url = self._CO_API_URL + '/identifiers.json'
+    resp = self._s.post(
+        url=url,
+        data=post_body
     )
     if resp.status_code == 201:
         return json.loads(resp.text)
diff --git a/examples/identifiers_example.py b/examples/identifiers_example.py
index 978521e..236d0cb 100644
--- a/examples/identifiers_example.py
+++ b/examples/identifiers_example.py
@@ -15,7 +15,13 @@
 # identifiers_add() -> dict
 print('### identifiers_add')
 try:
-    new_identifier = api.identifiers_add()
+    new_identifier = api.identifiers_add(
+        identity_type='eppn',
+        identifier='test@domain.com',
+        login_flag=False,
+        person_type='CO',
+        person_id=CO_PERSON_ID
+    )
     print(json.dumps(new_identifier, indent=4))
 except HTTPError as err:
     print('[ERROR] Exception caught')