diff --git a/tempest/common/credentials_factory.py b/tempest/common/credentials_factory.py
index 7c73ada..82db9cc 100644
--- a/tempest/common/credentials_factory.py
+++ b/tempest/common/credentials_factory.py
@@ -186,11 +186,6 @@
             params[attr] = getattr(_section, attr)
         else:
             params[attr] = getattr(_section, prefix + "_" + attr)
-    # NOTE(andreaf) v2 API still uses tenants, so we must translate project
-    # to tenant before building the Credentials object
-    if identity_version == 'v2':
-        params['tenant_name'] = params.get('project_name')
-        params.pop('project_name', None)
     # Build and validate credentials. We are reading configured credentials,
     # so validate them even if fill_in is False
     credentials = get_credentials(fill_in=fill_in,
diff --git a/tempest/common/preprov_creds.py b/tempest/common/preprov_creds.py
index 51f723b..7350222 100644
--- a/tempest/common/preprov_creds.py
+++ b/tempest/common/preprov_creds.py
@@ -43,6 +43,11 @@
 
 class PreProvisionedCredentialProvider(cred_provider.CredentialProvider):
 
+    # Exclude from the hash fields specific to v2 or v3 identity API
+    # i.e. only include user*, project*, tenant* and password
+    HASH_CRED_FIELDS = (set(auth.KeystoneV2Credentials.ATTRIBUTES) &
+                        set(auth.KeystoneV3Credentials.ATTRIBUTES))
+
     def __init__(self, identity_version, test_accounts_file,
                  accounts_lock_dir, name=None, credentials_domain=None,
                  admin_role=None, object_storage_operator_role=None,
@@ -104,6 +109,7 @@
                       object_storage_operator_role=None,
                       object_storage_reseller_admin_role=None):
         hash_dict = {'roles': {}, 'creds': {}, 'networks': {}}
+
         # Loop over the accounts read from the yaml file
         for account in accounts:
             roles = []
@@ -116,7 +122,9 @@
             if 'resources' in account:
                 resources = account.pop('resources')
             temp_hash = hashlib.md5()
-            temp_hash.update(six.text_type(account).encode('utf-8'))
+            account_for_hash = dict((k, v) for (k, v) in six.iteritems(account)
+                                    if k in cls.HASH_CRED_FIELDS)
+            temp_hash.update(six.text_type(account_for_hash).encode('utf-8'))
             temp_hash_key = temp_hash.hexdigest()
             hash_dict['creds'][temp_hash_key] = account
             for role in roles:
@@ -262,13 +270,13 @@
         for _hash in self.hash_dict['creds']:
             # Comparing on the attributes that are expected in the YAML
             init_attributes = creds.get_init_attributes()
+            # Only use the attributes initially used to calculate the hash
+            init_attributes = [x for x in init_attributes if
+                               x in self.HASH_CRED_FIELDS]
             hash_attributes = self.hash_dict['creds'][_hash].copy()
-            if ('user_domain_name' in init_attributes and 'user_domain_name'
-                    not in hash_attributes):
-                # Allow for the case of domain_name populated from config
-                domain_name = self.credentials_domain
-                hash_attributes['user_domain_name'] = domain_name
-            if all([getattr(creds, k) == hash_attributes[k] for
+            # NOTE(andreaf) Not all fields may be available on all credentials
+            # so defaulting to None for that case.
+            if all([getattr(creds, k, None) == hash_attributes.get(k, None) for
                    k in init_attributes]):
                 return _hash
         raise AttributeError('Invalid credentials %s' % creds)
@@ -351,23 +359,20 @@
         return net_creds
 
     def _extend_credentials(self, creds_dict):
-        # In case of v3, adds a user_domain_name field to the creds
-        # dict if not defined
+        # Add or remove credential domain fields to fit the identity version
+        domain_fields = set(x for x in auth.KeystoneV3Credentials.ATTRIBUTES
+                            if 'domain' in x)
+        msg = 'Assuming they are valid in the default domain.'
         if self.identity_version == 'v3':
-            user_domain_fields = set(['user_domain_name', 'user_domain_id'])
-            if not user_domain_fields.intersection(set(creds_dict.keys())):
-                creds_dict['user_domain_name'] = self.credentials_domain
-        # NOTE(andreaf) In case of v2, replace project with tenant if project
-        # is provided and tenant is not
+            if not domain_fields.intersection(set(creds_dict.keys())):
+                msg = 'Using credentials %s for v3 API calls. ' + msg
+                LOG.warning(msg, self._sanitize_creds(creds_dict))
+                creds_dict['domain_name'] = self.credentials_domain
         if self.identity_version == 'v2':
-            if ('project_name' in creds_dict and
-                    'tenant_name' in creds_dict and
-                    creds_dict['project_name'] != creds_dict['tenant_name']):
-                clean_creds = self._sanitize_creds(creds_dict)
-                msg = 'Cannot specify project and tenant at the same time %s'
-                raise exceptions.InvalidCredentials(msg % clean_creds)
-            if ('project_name' in creds_dict and
-                    'tenant_name' not in creds_dict):
-                creds_dict['tenant_name'] = creds_dict['project_name']
-                creds_dict.pop('project_name')
+            if domain_fields.intersection(set(creds_dict.keys())):
+                msg = 'Using credentials %s for v2 API calls. ' + msg
+                LOG.warning(msg, self._sanitize_creds(creds_dict))
+            # Remove all valid domain attributes
+            for attr in domain_fields.intersection(set(creds_dict.keys())):
+                creds_dict.pop(attr)
         return creds_dict
diff --git a/tempest/lib/auth.py b/tempest/lib/auth.py
index a6833be..c2ccf77 100644
--- a/tempest/lib/auth.py
+++ b/tempest/lib/auth.py
@@ -532,6 +532,7 @@
     """
 
     ATTRIBUTES = []
+    COLLISIONS = []
 
     def __init__(self, **kwargs):
         """Enforce the available attributes at init time (only).
@@ -543,6 +544,13 @@
         self._apply_credentials(kwargs)
 
     def _apply_credentials(self, attr):
+        for (key1, key2) in self.COLLISIONS:
+            val1 = attr.get(key1)
+            val2 = attr.get(key2)
+            if val1 and val2 and val1 != val2:
+                msg = ('Cannot have conflicting values for %s and %s' %
+                       (key1, key2))
+                raise exceptions.InvalidCredentials(msg)
         for key in attr.keys():
             if key in self.ATTRIBUTES:
                 setattr(self, key, attr[key])
@@ -600,7 +608,33 @@
 class KeystoneV2Credentials(Credentials):
 
     ATTRIBUTES = ['username', 'password', 'tenant_name', 'user_id',
-                  'tenant_id']
+                  'tenant_id', 'project_id', 'project_name']
+    COLLISIONS = [('project_name', 'tenant_name'), ('project_id', 'tenant_id')]
+
+    def __str__(self):
+        """Represent only attributes included in self.ATTRIBUTES"""
+        attrs = [attr for attr in self.ATTRIBUTES if attr is not 'password']
+        _repr = dict((k, getattr(self, k)) for k in attrs)
+        return str(_repr)
+
+    def __setattr__(self, key, value):
+        # NOTE(andreaf) In order to ease the migration towards 'project' we
+        # support v2 credentials configured with 'project' and translate it
+        # to tenant on the fly. The original kwargs are stored for clients
+        # that may rely on them. We also set project when tenant is defined
+        # so clients can rely on project being part of credentials.
+        parent = super(KeystoneV2Credentials, self)
+        # for project_* set tenant only
+        if key == 'project_id':
+            parent.__setattr__('tenant_id', value)
+        elif key == 'project_name':
+            parent.__setattr__('tenant_name', value)
+        if key == 'tenant_id':
+            parent.__setattr__('project_id', value)
+        elif key == 'tenant_name':
+            parent.__setattr__('project_name', value)
+        # trigger default behaviour for all attributes
+        parent.__setattr__(key, value)
 
     def is_valid(self):
         """Check of credentials (no API call)
@@ -611,9 +645,6 @@
         return None not in (self.username, self.password)
 
 
-COLLISIONS = [('project_name', 'tenant_name'), ('project_id', 'tenant_id')]
-
-
 class KeystoneV3Credentials(Credentials):
     """Credentials suitable for the Keystone Identity V3 API"""
 
@@ -621,16 +652,7 @@
                   'project_domain_id', 'project_domain_name', 'project_id',
                   'project_name', 'tenant_id', 'tenant_name', 'user_domain_id',
                   'user_domain_name', 'user_id']
-
-    def _apply_credentials(self, attr):
-        for (key1, key2) in COLLISIONS:
-            val1 = attr.get(key1)
-            val2 = attr.get(key2)
-            if val1 and val2 and val1 != val2:
-                msg = ('Cannot have conflicting values for %s and %s' %
-                       (key1, key2))
-                raise exceptions.InvalidCredentials(msg)
-        super(KeystoneV3Credentials, self)._apply_credentials(attr)
+    COLLISIONS = [('project_name', 'tenant_name'), ('project_id', 'tenant_id')]
 
     def __setattr__(self, key, value):
         parent = super(KeystoneV3Credentials, self)
diff --git a/tempest/tests/common/test_preprov_creds.py b/tempest/tests/common/test_preprov_creds.py
index b595c88..22bbdd3 100644
--- a/tempest/tests/common/test_preprov_creds.py
+++ b/tempest/tests/common/test_preprov_creds.py
@@ -27,7 +27,6 @@
 from tempest import config
 from tempest.lib import auth
 from tempest.lib import exceptions as lib_exc
-from tempest.lib.services.identity.v2 import token_client
 from tempest.tests import base
 from tempest.tests import fake_config
 from tempest.tests.lib import fake_identity
@@ -43,40 +42,46 @@
                     'object_storage_operator_role': 'operator',
                     'object_storage_reseller_admin_role': 'reseller'}
 
+    identity_response = fake_identity._fake_v2_response
+    token_client = ('tempest.lib.services.identity.v2.token_client'
+                    '.TokenClient.raw_request')
+
+    @classmethod
+    def _fake_accounts(cls, admin_role):
+        return [
+            {'username': 'test_user1', 'tenant_name': 'test_tenant1',
+             'password': 'p'},
+            {'username': 'test_user2', 'project_name': 'test_tenant2',
+             'password': 'p'},
+            {'username': 'test_user3', 'tenant_name': 'test_tenant3',
+             'password': 'p'},
+            {'username': 'test_user4', 'project_name': 'test_tenant4',
+             'password': 'p'},
+            {'username': 'test_user5', 'tenant_name': 'test_tenant5',
+             'password': 'p'},
+            {'username': 'test_user6', 'project_name': 'test_tenant6',
+             'password': 'p', 'roles': ['role1', 'role2']},
+            {'username': 'test_user7', 'tenant_name': 'test_tenant7',
+             'password': 'p', 'roles': ['role2', 'role3']},
+            {'username': 'test_user8', 'project_name': 'test_tenant8',
+             'password': 'p', 'roles': ['role4', 'role1']},
+            {'username': 'test_user9', 'tenant_name': 'test_tenant9',
+             'password': 'p', 'roles': ['role1', 'role2', 'role3', 'role4']},
+            {'username': 'test_user10', 'project_name': 'test_tenant10',
+             'password': 'p', 'roles': ['role1', 'role2', 'role3', 'role4']},
+            {'username': 'test_user11', 'tenant_name': 'test_tenant11',
+             'password': 'p', 'roles': [admin_role]},
+            {'username': 'test_user12', 'project_name': 'test_tenant12',
+             'password': 'p', 'roles': [admin_role]}]
+
     def setUp(self):
         super(TestPreProvisionedCredentials, self).setUp()
         self.useFixture(fake_config.ConfigFixture())
         self.patchobject(config, 'TempestConfigPrivate',
                          fake_config.FakePrivate)
-        self.patchobject(token_client.TokenClient, 'raw_request',
-                         fake_identity._fake_v2_response)
+        self.patch(self.token_client, side_effect=self.identity_response)
         self.useFixture(lockutils_fixtures.ExternalLockFixture())
-        self.test_accounts = [
-            {'username': 'test_user1', 'tenant_name': 'test_tenant1',
-             'password': 'p'},
-            {'username': 'test_user2', 'tenant_name': 'test_tenant2',
-             'password': 'p'},
-            {'username': 'test_user3', 'tenant_name': 'test_tenant3',
-             'password': 'p'},
-            {'username': 'test_user4', 'tenant_name': 'test_tenant4',
-             'password': 'p'},
-            {'username': 'test_user5', 'tenant_name': 'test_tenant5',
-             'password': 'p'},
-            {'username': 'test_user6', 'tenant_name': 'test_tenant6',
-             'password': 'p', 'roles': ['role1', 'role2']},
-            {'username': 'test_user7', 'tenant_name': 'test_tenant7',
-             'password': 'p', 'roles': ['role2', 'role3']},
-            {'username': 'test_user8', 'tenant_name': 'test_tenant8',
-             'password': 'p', 'roles': ['role4', 'role1']},
-            {'username': 'test_user9', 'tenant_name': 'test_tenant9',
-             'password': 'p', 'roles': ['role1', 'role2', 'role3', 'role4']},
-            {'username': 'test_user10', 'tenant_name': 'test_tenant10',
-             'password': 'p', 'roles': ['role1', 'role2', 'role3', 'role4']},
-            {'username': 'test_user11', 'tenant_name': 'test_tenant11',
-             'password': 'p', 'roles': [cfg.CONF.identity.admin_role]},
-            {'username': 'test_user12', 'tenant_name': 'test_tenant12',
-             'password': 'p', 'roles': [cfg.CONF.identity.admin_role]},
-        ]
+        self.test_accounts = self._fake_accounts(cfg.CONF.identity.admin_role)
         self.accounts_mock = self.useFixture(mockpatch.Patch(
             'tempest.common.preprov_creds.read_accounts_yaml',
             return_value=self.test_accounts))
@@ -89,24 +94,33 @@
 
     def _get_hash_list(self, accounts_list):
         hash_list = []
+        hash_fields = (
+            preprov_creds.PreProvisionedCredentialProvider.HASH_CRED_FIELDS)
         for account in accounts_list:
             hash = hashlib.md5()
-            hash.update(six.text_type(account).encode('utf-8'))
+            account_for_hash = dict((k, v) for (k, v) in six.iteritems(account)
+                                    if k in hash_fields)
+            hash.update(six.text_type(account_for_hash).encode('utf-8'))
             temp_hash = hash.hexdigest()
             hash_list.append(temp_hash)
         return hash_list
 
     def test_get_hash(self):
-        self.patchobject(token_client.TokenClient, 'raw_request',
-                         fake_identity._fake_v2_response)
-        test_account_class = preprov_creds.PreProvisionedCredentialProvider(
-            **self.fixed_params)
-        hash_list = self._get_hash_list(self.test_accounts)
-        test_cred_dict = self.test_accounts[3]
-        test_creds = auth.get_credentials(fake_identity.FAKE_AUTH_URL,
-                                          **test_cred_dict)
-        results = test_account_class.get_hash(test_creds)
-        self.assertEqual(hash_list[3], results)
+        # Test with all accounts to make sure we try all combinations
+        # and hide no race conditions
+        hash_index = 0
+        for test_cred_dict in self.test_accounts:
+            test_account_class = (
+                preprov_creds.PreProvisionedCredentialProvider(
+                    **self.fixed_params))
+            hash_list = self._get_hash_list(self.test_accounts)
+            test_creds = auth.get_credentials(
+                fake_identity.FAKE_AUTH_URL,
+                identity_version=self.fixed_params['identity_version'],
+                **test_cred_dict)
+            results = test_account_class.get_hash(test_creds)
+            self.assertEqual(hash_list[hash_index], results)
+            hash_index += 1
 
     def test_get_hash_dict(self):
         test_account_class = preprov_creds.PreProvisionedCredentialProvider(
@@ -331,3 +345,53 @@
         self.assertIn('id', network)
         self.assertEqual('fake-id', network['id'])
         self.assertEqual('network-2', network['name'])
+
+
+class TestPreProvisionedCredentialsV3(TestPreProvisionedCredentials):
+
+    fixed_params = {'name': 'test class',
+                    'identity_version': 'v3',
+                    'test_accounts_file': 'fake_accounts_file',
+                    'accounts_lock_dir': 'fake_locks_dir',
+                    'admin_role': 'admin',
+                    'object_storage_operator_role': 'operator',
+                    'object_storage_reseller_admin_role': 'reseller'}
+
+    identity_response = fake_identity._fake_v3_response
+    token_client = ('tempest.lib.services.identity.v3.token_client'
+                    '.V3TokenClient.raw_request')
+
+    @classmethod
+    def _fake_accounts(cls, admin_role):
+        return [
+            {'username': 'test_user1', 'project_name': 'test_project1',
+             'domain_name': 'domain', 'password': 'p'},
+            {'username': 'test_user2', 'project_name': 'test_project2',
+             'domain_name': 'domain', 'password': 'p'},
+            {'username': 'test_user3', 'project_name': 'test_project3',
+             'domain_name': 'domain', 'password': 'p'},
+            {'username': 'test_user4', 'project_name': 'test_project4',
+             'domain_name': 'domain', 'password': 'p'},
+            {'username': 'test_user5', 'project_name': 'test_project5',
+             'domain_name': 'domain', 'password': 'p'},
+            {'username': 'test_user6', 'project_name': 'test_project6',
+             'domain_name': 'domain', 'password': 'p',
+             'roles': ['role1', 'role2']},
+            {'username': 'test_user7', 'project_name': 'test_project7',
+             'domain_name': 'domain', 'password': 'p',
+             'roles': ['role2', 'role3']},
+            {'username': 'test_user8', 'project_name': 'test_project8',
+             'domain_name': 'domain', 'password': 'p',
+             'roles': ['role4', 'role1']},
+            {'username': 'test_user9', 'project_name': 'test_project9',
+             'domain_name': 'domain', 'password': 'p',
+             'roles': ['role1', 'role2', 'role3', 'role4']},
+            {'username': 'test_user10', 'project_name': 'test_project10',
+             'domain_name': 'domain', 'password': 'p',
+             'roles': ['role1', 'role2', 'role3', 'role4']},
+            {'username': 'test_user11', 'project_name': 'test_project11',
+             'domain_name': 'domain', 'password': 'p',
+             'roles': [admin_role]},
+            {'username': 'test_user12', 'project_name': 'test_project12',
+             'domain_name': 'domain', 'password': 'p',
+             'roles': [admin_role]}]
diff --git a/tempest/tests/lib/test_credentials.py b/tempest/tests/lib/test_credentials.py
index ca3baa1..b6f2cf6 100644
--- a/tempest/tests/lib/test_credentials.py
+++ b/tempest/tests/lib/test_credentials.py
@@ -36,8 +36,10 @@
         # Check the right version of credentials has been returned
         self.assertIsInstance(credentials, credentials_class)
         # Check the id attributes are filled in
+        # NOTE(andreaf) project_* attributes are accepted as input but
+        # never set on the credentials object
         attributes = [x for x in credentials.ATTRIBUTES if (
-            '_id' in x and x != 'domain_id')]
+            '_id' in x and x != 'domain_id' and x != 'project_id')]
         for attr in attributes:
             if filled:
                 self.assertIsNotNone(getattr(credentials, attr))