diff --git a/system_tests/bigquery.py b/system_tests/bigquery.py
index dee49786cac1..ac350ad83ca7 100644
--- a/system_tests/bigquery.py
+++ b/system_tests/bigquery.py
@@ -21,8 +21,10 @@
 from gcloud.environment_vars import TESTS_PROJECT
 from gcloud import bigquery
 
+from system_test_utils import unique_resource_id
 
-DATASET_NAME = 'system_tests_%012d' % (1000 * time.time(),)
+
+DATASET_NAME = 'system_tests' + unique_resource_id()
 
 
 class Config(object):
@@ -97,9 +99,9 @@ def test_update_dataset(self):
 
     def test_list_datasets(self):
         datasets_to_create = [
-            'new%d' % (1000 * time.time(),),
-            'newer%d' % (1000 * time.time(),),
-            'newest%d' % (1000 * time.time(),),
+            'new' + unique_resource_id(),
+            'newer' + unique_resource_id(),
+            'newest' + unique_resource_id(),
         ]
         for dataset_name in datasets_to_create:
             dataset = Config.CLIENT.dataset(dataset_name)
@@ -143,9 +145,9 @@ def test_list_tables(self):
 
         # Insert some tables to be listed.
         tables_to_create = [
-            'new%d' % (1000 * time.time(),),
-            'newer%d' % (1000 * time.time(),),
-            'newest%d' % (1000 * time.time(),),
+            'new' + unique_resource_id(),
+            'newer' + unique_resource_id(),
+            'newest' + unique_resource_id(),
         ]
         full_name = bigquery.SchemaField('full_name', 'STRING',
                                          mode='REQUIRED')
@@ -259,8 +261,8 @@ def test_load_table_from_storage_then_dump_table(self):
         import csv
         import tempfile
         from gcloud.storage import Client as StorageClient
-        TIMESTAMP = 1000 * time.time()
-        BUCKET_NAME = 'bq_load_test_%d' % (TIMESTAMP,)
+        local_id = unique_resource_id()
+        BUCKET_NAME = 'bq_load_test' + local_id
         BLOB_NAME = 'person_ages.csv'
         GS_URL = 'gs://%s/%s' % (BUCKET_NAME, BLOB_NAME)
         ROWS = [
@@ -301,7 +303,7 @@ def test_load_table_from_storage_then_dump_table(self):
         self.to_delete.insert(0, table)
 
         job = Config.CLIENT.load_table_from_storage(
-            'bq_load_storage_test_%d' % (TIMESTAMP,), table, GS_URL)
+            'bq_load_storage_test_' + local_id, table, GS_URL)
         job.create_disposition = 'CREATE_NEVER'
         job.skip_leading_rows = 1
         job.source_format = 'CSV'
diff --git a/system_tests/bigtable.py b/system_tests/bigtable.py
index 39d60e0658f6..5fdd250c3350 100644
--- a/system_tests/bigtable.py
+++ b/system_tests/bigtable.py
@@ -32,11 +32,11 @@
 from gcloud.bigtable.row_data import PartialRowData
 from gcloud.environment_vars import TESTS_PROJECT
 
+from system_test_utils import unique_resource_id
+
 
-_helpers.PROJECT = TESTS_PROJECT
 CENTRAL_1C_ZONE = 'us-central1-c'
-NOW_MILLIS = int(1000 * time.time())
-CLUSTER_ID = 'gcloud-python-%d' % (NOW_MILLIS,)
+CLUSTER_ID = 'gcloud-py' + unique_resource_id('-')
 TABLE_ID = 'gcloud-python-test-table'
 COLUMN_FAMILY_ID1 = u'col-fam-id1'
 COLUMN_FAMILY_ID2 = u'col-fam-id2'
@@ -89,6 +89,7 @@ def _operation_wait(operation, max_attempts=5):
 
 
 def setUpModule():
+    _helpers.PROJECT = TESTS_PROJECT
     Config.CLIENT = Client(admin=True)
     Config.CLUSTER = Config.CLIENT.cluster(CENTRAL_1C_ZONE, CLUSTER_ID,
                                            display_name=CLUSTER_ID)
diff --git a/system_tests/bigtable_happybase.py b/system_tests/bigtable_happybase.py
index a0f3366d7e2d..90c35a99fe5c 100644
--- a/system_tests/bigtable_happybase.py
+++ b/system_tests/bigtable_happybase.py
@@ -15,7 +15,6 @@
 
 import operator
 import struct
-import time
 
 import unittest2
 
@@ -24,13 +23,15 @@
 from gcloud.bigtable.happybase.connection import Connection
 from gcloud.environment_vars import TESTS_PROJECT
 
+from bigtable import _operation_wait
+from system_test_utils import unique_resource_id
+
 
 _PACK_I64 = struct.Struct('>q').pack
 _FIRST_ELT = operator.itemgetter(0)
 _helpers.PROJECT = TESTS_PROJECT
 ZONE = 'us-central1-c'
-NOW_MILLIS = int(1000 * time.time())
-CLUSTER_ID = 'gcloud-python-%d' % (NOW_MILLIS,)
+CLUSTER_ID = 'gcloud-py' + unique_resource_id('-')
 TABLE_NAME = 'table-name'
 ALT_TABLE_NAME = 'other-table'
 TTL_FOR_TEST = 3
@@ -61,26 +62,6 @@ class Config(object):
     TABLE = None
 
 
-def _operation_wait(operation, max_attempts=5):
-    """Wait until an operation has completed.
-
-    :type operation: :class:`gcloud.bigtable.cluster.Operation`
-    :param operation: Operation that has not finished.
-
-    :type max_attempts: int
-    :param max_attempts: (Optional) The maximum number of times to check if
-                         the operation has finished. Defaults to 5.
-    """
-    total_sleep = 0
-    while not operation.finished():
-        if total_sleep > max_attempts:
-            return False
-        time.sleep(1)
-        total_sleep += 1
-
-    return True
-
-
 def set_connection():
     client = client_mod.Client(admin=True)
     cluster = client.cluster(ZONE, CLUSTER_ID)
@@ -646,7 +627,7 @@ def test_put_with_timestamp(self):
         value1 = 'value1'
         value2 = 'value2'
         row1_data = {COL1: value1, COL2: value2}
-        ts = NOW_MILLIS
+        ts = 1461367402
 
         # Need to clean-up row1 after.
         self.rows_to_delete.append(ROW_KEY1)
diff --git a/system_tests/clear_datastore.py b/system_tests/clear_datastore.py
index 922802d32af2..02467b1b9351 100644
--- a/system_tests/clear_datastore.py
+++ b/system_tests/clear_datastore.py
@@ -25,13 +25,13 @@
 
 
 FETCH_MAX = 20
-ALL_KINDS = [
+ALL_KINDS = (
     'Character',
     'Company',
     'Kind',
     'Person',
     'Post',
-]
+)
 TRANSACTION_MAX_GROUPS = 5
 
 
@@ -98,7 +98,7 @@ def remove_all_entities(client=None):
 if __name__ == '__main__':
     print_func('This command will remove all entities for '
                'the following kinds:')
-    print_func('\n'.join(['- ' + val for val in ALL_KINDS]))
+    print_func('\n'.join('- ' + val for val in ALL_KINDS))
     response = six.moves.input('Is this OK [y/n]? ')
     if response.lower() == 'y':
         remove_all_entities()
diff --git a/system_tests/datastore.py b/system_tests/datastore.py
index 521c727a4c93..e74f316423fe 100644
--- a/system_tests/datastore.py
+++ b/system_tests/datastore.py
@@ -14,7 +14,6 @@
 
 import datetime
 import os
-import time
 
 import httplib2
 import unittest2
@@ -26,11 +25,11 @@
 from gcloud.environment_vars import GCD_DATASET
 from gcloud.environment_vars import TESTS_PROJECT
 from gcloud.exceptions import Conflict
-# This assumes the command is being run via tox hence the
-# repository root is the current directory.
+
 import clear_datastore
 import populate_datastore
 from system_test_utils import EmulatorCreds
+from system_test_utils import unique_resource_id
 
 
 class Config(object):
@@ -54,7 +53,7 @@ def clone_client(client):
 def setUpModule():
     emulator_dataset = os.getenv(GCD_DATASET)
     # Isolated namespace so concurrent test runs don't collide.
-    test_namespace = 'ns%d' % (1000 * time.time(),)
+    test_namespace = 'ns' + unique_resource_id()
     if emulator_dataset is None:
         _helpers.PROJECT = TESTS_PROJECT
         Config.CLIENT = datastore.Client(namespace=test_namespace)
diff --git a/system_tests/logging_.py b/system_tests/logging_.py
index 9e3c02de30e6..8a69624d2baa 100644
--- a/system_tests/logging_.py
+++ b/system_tests/logging_.py
@@ -20,15 +20,17 @@
 from gcloud.environment_vars import TESTS_PROJECT
 from gcloud import logging
 
+from system_test_utils import unique_resource_id
 
-_MILLIS = 1000 * time.time()
-DEFAULT_METRIC_NAME = 'system-tests-metric-%d' % (_MILLIS,)
-DEFAULT_SINK_NAME = 'system-tests-sink-%d' % (_MILLIS,)
+
+_RESOURCE_ID = unique_resource_id('-')
+DEFAULT_METRIC_NAME = 'system-tests-metric%s' % (_RESOURCE_ID,)
+DEFAULT_SINK_NAME = 'system-tests-sink%s' % (_RESOURCE_ID,)
 DEFAULT_FILTER = 'logName:syslog AND severity>=INFO'
 DEFAULT_DESCRIPTION = 'System testing'
-BUCKET_NAME = 'gcloud-python-system-testing-%d' % (_MILLIS,)
-DATASET_NAME = 'system_testing_dataset_%d' % (_MILLIS,)
-TOPIC_NAME = 'gcloud-python-system-testing-%d' % (_MILLIS,)
+BUCKET_NAME = 'gcloud-python-system-testing%s' % (_RESOURCE_ID,)
+DATASET_NAME = ('system_testing_dataset' + _RESOURCE_ID).replace('-', '_')
+TOPIC_NAME = 'gcloud-python-system-testing%s' % (_RESOURCE_ID,)
 
 
 class Config(object):
@@ -66,8 +68,7 @@ def tearDown(self):
 
     @staticmethod
     def _logger_name():
-        _millis = 1000 * time.time()
-        return 'system-tests-logger-%d' % (_millis,)
+        return 'system-tests-logger' + unique_resource_id('-')
 
     def test_log_text(self):
         TEXT_PAYLOAD = 'System test: test_log_text'
diff --git a/system_tests/populate_datastore.py b/system_tests/populate_datastore.py
index 6a6679ff521a..a4e68d1a5e8b 100644
--- a/system_tests/populate_datastore.py
+++ b/system_tests/populate_datastore.py
@@ -28,7 +28,7 @@
 ANCESTOR = ('Book', 'GoT')
 RICKARD = ANCESTOR + ('Character', 'Rickard')
 EDDARD = RICKARD + ('Character', 'Eddard')
-KEY_PATHS = [
+KEY_PATHS = (
     RICKARD,
     EDDARD,
     ANCESTOR + ('Character', 'Catelyn'),
@@ -37,8 +37,8 @@
     EDDARD + ('Character', 'Robb'),
     EDDARD + ('Character', 'Bran'),
     EDDARD + ('Character', 'Jon Snow'),
-]
-CHARACTERS = [
+)
+CHARACTERS = (
     {
         'name': u'Rickard',
         'family': u'Stark',
@@ -80,7 +80,7 @@
         'appearances': 32,
         'alive': True,
     },
-]
+)
 
 
 def print_func(message):
diff --git a/system_tests/pubsub.py b/system_tests/pubsub.py
index 9786ca372239..9f6ababdc7a5 100644
--- a/system_tests/pubsub.py
+++ b/system_tests/pubsub.py
@@ -22,10 +22,12 @@
 from gcloud.environment_vars import PUBSUB_EMULATOR
 from gcloud.environment_vars import TESTS_PROJECT
 from gcloud import pubsub
+
 from system_test_utils import EmulatorCreds
+from system_test_utils import unique_resource_id
 
 
-DEFAULT_TOPIC_NAME = 'subscribe-me%d' % (1000 * time.time(),)
+DEFAULT_TOPIC_NAME = 'subscribe-me' + unique_resource_id('-')
 
 
 class Config(object):
@@ -58,7 +60,7 @@ def tearDown(self):
             doomed.delete()
 
     def test_create_topic(self):
-        topic_name = 'a-new-topic%d' % (1000 * time.time(),)
+        topic_name = 'a-new-topic' + unique_resource_id('-')
         topic = Config.CLIENT.topic(topic_name)
         self.assertFalse(topic.exists())
         topic.create()
@@ -68,9 +70,9 @@ def test_create_topic(self):
 
     def test_list_topics(self):
         topics_to_create = [
-            'new%d' % (1000 * time.time(),),
-            'newer%d' % (1000 * time.time(),),
-            'newest%d' % (1000 * time.time(),),
+            'new' + unique_resource_id(),
+            'newer' + unique_resource_id(),
+            'newest' + unique_resource_id(),
         ]
         for topic_name in topics_to_create:
             topic = Config.CLIENT.topic(topic_name)
@@ -89,7 +91,7 @@ def test_create_subscription_defaults(self):
         self.assertFalse(topic.exists())
         topic.create()
         self.to_delete.append(topic)
-        SUBSCRIPTION_NAME = 'subscribing-now-%d' % (1000 * time.time(),)
+        SUBSCRIPTION_NAME = 'subscribing-now' + unique_resource_id('-')
         subscription = topic.subscription(SUBSCRIPTION_NAME)
         self.assertFalse(subscription.exists())
         subscription.create()
@@ -103,7 +105,7 @@ def test_create_subscription_w_ack_deadline(self):
         self.assertFalse(topic.exists())
         topic.create()
         self.to_delete.append(topic)
-        SUBSCRIPTION_NAME = 'subscribing-now-%d' % (1000 * time.time(),)
+        SUBSCRIPTION_NAME = 'subscribing-now' + unique_resource_id()
         subscription = topic.subscription(SUBSCRIPTION_NAME, ack_deadline=120)
         self.assertFalse(subscription.exists())
         subscription.create()
@@ -121,9 +123,9 @@ def test_list_subscriptions(self):
         empty, _ = topic.list_subscriptions()
         self.assertEqual(len(empty), 0)
         subscriptions_to_create = [
-            'new%d' % (1000 * time.time(),),
-            'newer%d' % (1000 * time.time(),),
-            'newest%d' % (1000 * time.time(),),
+            'new' + unique_resource_id(),
+            'newer' + unique_resource_id(),
+            'newest' + unique_resource_id(),
         ]
         for subscription_name in subscriptions_to_create:
             subscription = topic.subscription(subscription_name)
@@ -142,7 +144,7 @@ def test_message_pull_mode_e2e(self):
         self.assertFalse(topic.exists())
         topic.create()
         self.to_delete.append(topic)
-        SUBSCRIPTION_NAME = 'subscribing-now-%d' % (1000 * time.time(),)
+        SUBSCRIPTION_NAME = 'subscribing-now' + unique_resource_id('-')
         subscription = topic.subscription(SUBSCRIPTION_NAME)
         self.assertFalse(subscription.exists())
         subscription.create()
@@ -170,7 +172,7 @@ def _by_timestamp(message):
         self.assertEqual(message2.attributes['extra'], EXTRA_2)
 
     def test_topic_iam_policy(self):
-        topic_name = 'test-topic-iam-policy-topic-%d' % (1000 * time.time(),)
+        topic_name = 'test-topic-iam-policy-topic' + unique_resource_id('-')
         topic = Config.CLIENT.topic(topic_name)
         topic.create()
         count = 5
@@ -185,7 +187,7 @@ def test_topic_iam_policy(self):
         self.assertEqual(new_policy.viewers, policy.viewers)
 
     def test_subscription_iam_policy(self):
-        topic_name = 'test-sub-iam-policy-topic-%d' % (1000 * time.time(),)
+        topic_name = 'test-sub-iam-policy-topic' + unique_resource_id('-')
         topic = Config.CLIENT.topic(topic_name)
         topic.create()
         count = 5
@@ -194,7 +196,7 @@ def test_subscription_iam_policy(self):
             count -= 1
         self.assertTrue(topic.exists())
         self.to_delete.append(topic)
-        SUB_NAME = 'test-sub-iam-policy-sub-%d' % (1000 * time.time(),)
+        SUB_NAME = 'test-sub-iam-policy-sub' + unique_resource_id('-')
         subscription = topic.subscription(SUB_NAME)
         subscription.create()
         count = 5
@@ -209,8 +211,8 @@ def test_subscription_iam_policy(self):
         self.assertEqual(new_policy.viewers, policy.viewers)
 
     def test_fetch_delete_subscription_w_deleted_topic(self):
-        TO_DELETE = 'delete-me-%d' % (1000 * time.time(),)
-        ORPHANED = 'orphaned-%d' % (1000 * time.time(),)
+        TO_DELETE = 'delete-me' + unique_resource_id('-')
+        ORPHANED = 'orphaned' + unique_resource_id('-')
         topic = Config.CLIENT.topic(TO_DELETE)
         topic.create()
         subscription = topic.subscription(ORPHANED)
diff --git a/system_tests/run_emulator.py b/system_tests/run_emulator.py
index c77f7c277240..c3ea8fdcc602 100644
--- a/system_tests/run_emulator.py
+++ b/system_tests/run_emulator.py
@@ -62,7 +62,7 @@ def get_start_command(package):
     :rtype: tuple
     :returns: The arguments to be used, in a tuple.
     """
-    return ('gcloud', 'beta', 'emulators', package, 'start')
+    return 'gcloud', 'beta', 'emulators', package, 'start'
 
 
 def get_env_init_command(package):
@@ -74,7 +74,7 @@ def get_env_init_command(package):
     :rtype: tuple
     :returns: The arguments to be used, in a tuple.
     """
-    return ('gcloud', 'beta', 'emulators', package, 'env-init')
+    return 'gcloud', 'beta', 'emulators', package, 'env-init'
 
 
 def datastore_wait_ready(popen):
diff --git a/system_tests/run_system_test.py b/system_tests/run_system_test.py
index 6369a9bb7227..fd2d1967f982 100644
--- a/system_tests/run_system_test.py
+++ b/system_tests/run_system_test.py
@@ -16,8 +16,6 @@
 import sys
 import unittest2
 
-# This assumes the command is being run via tox hence the
-# repository root is the current directory.
 import bigquery
 import bigtable
 import bigtable_happybase
diff --git a/system_tests/storage.py b/system_tests/storage.py
index a94233dac841..68edfee28db9 100644
--- a/system_tests/storage.py
+++ b/system_tests/storage.py
@@ -26,6 +26,8 @@
 from gcloud import storage
 from gcloud.storage._helpers import _base64_md5hash
 
+from system_test_utils import unique_resource_id
+
 
 HTTP = httplib2.Http()
 _helpers.PROJECT = TESTS_PROJECT
@@ -43,8 +45,7 @@ class Config(object):
 
 def setUpModule():
     Config.CLIENT = storage.Client()
-    # %d rounds milliseconds to nearest integer.
-    bucket_name = 'new%d' % (1000 * time.time(),)
+    bucket_name = 'new' + unique_resource_id()
     # In the **very** rare case the bucket name is reserved, this
     # fails with a ConnectionError.
     Config.TEST_BUCKET = Config.CLIENT.create_bucket(bucket_name)
@@ -65,7 +66,7 @@ def tearDown(self):
                 Config.CLIENT.bucket(bucket_name).delete()
 
     def test_create_bucket(self):
-        new_bucket_name = 'a-new-bucket'
+        new_bucket_name = 'a-new-bucket' + unique_resource_id('-')
         self.assertRaises(exceptions.NotFound,
                           Config.CLIENT.get_bucket, new_bucket_name)
         created = Config.CLIENT.create_bucket(new_bucket_name)
@@ -74,9 +75,9 @@ def test_create_bucket(self):
 
     def test_list_buckets(self):
         buckets_to_create = [
-            'new%d' % (1000 * time.time(),),
-            'newer%d' % (1000 * time.time(),),
-            'newest%d' % (1000 * time.time(),),
+            'new' + unique_resource_id(),
+            'newer' + unique_resource_id(),
+            'newest' + unique_resource_id(),
         ]
         created_buckets = []
         for bucket_name in buckets_to_create:
@@ -193,7 +194,7 @@ def test_copy_existing_file(self):
 
 class TestStorageListFiles(TestStorageFiles):
 
-    FILENAMES = ['CloudLogo1', 'CloudLogo2', 'CloudLogo3']
+    FILENAMES = ('CloudLogo1', 'CloudLogo2', 'CloudLogo3')
 
     @classmethod
     def setUpClass(cls):
@@ -238,14 +239,14 @@ def test_paginate_files(self):
 
 class TestStoragePseudoHierarchy(TestStorageFiles):
 
-    FILENAMES = [
+    FILENAMES = (
         'file01.txt',
         'parent/file11.txt',
         'parent/child/file21.txt',
         'parent/child/file22.txt',
         'parent/child/grand/file31.txt',
         'parent/child/other/file32.txt',
-        ]
+    )
 
     @classmethod
     def setUpClass(cls):
diff --git a/system_tests/system_test_utils.py b/system_tests/system_test_utils.py
index d936bd05cd74..2050d04d2e08 100644
--- a/system_tests/system_test_utils.py
+++ b/system_tests/system_test_utils.py
@@ -15,6 +15,7 @@
 from __future__ import print_function
 import os
 import sys
+import time
 
 from gcloud.environment_vars import CREDENTIALS as TEST_CREDENTIALS
 from gcloud.environment_vars import TESTS_PROJECT
@@ -56,3 +57,17 @@ def check_environ():
     if missing:
         print(ENVIRON_ERROR_MSG % ', '.join(missing), file=sys.stderr)
         sys.exit(1)
+
+
+def unique_resource_id(delimiter='_'):
+    """A unique identifier for a resource.
+
+    Intended to help locate resources created in particular
+    testing environments and at particular times.
+    """
+    build_id = os.getenv('TRAVIS_BUILD_ID', '')
+    if build_id == '':
+        return '%s%d' % (delimiter, 1000 * time.time())
+    else:
+        return '%s%d%s%s' % (delimiter, time.time(),
+                             delimiter, build_id)