diff --git a/IPython/parallel/apps/clusterdir.py b/IPython/parallel/apps/clusterdir.py
index b707c02..c82a47a 100755
--- a/IPython/parallel/apps/clusterdir.py
+++ b/IPython/parallel/apps/clusterdir.py
@@ -36,7 +36,7 @@ from IPython.utils.path import (
     get_ipython_dir,
     expand_path
 )
-from IPython.utils.traitlets import Unicode, Bool, CStr, Instance, Dict
+from IPython.utils.traitlets import Unicode, Bool, Instance, Dict
 
 #-----------------------------------------------------------------------------
 # Module errors
@@ -360,8 +360,8 @@ class ClusterApplication(BaseIPythonApplication):
     clean_logs = Bool(False, shortname='--clean-logs', config=True,
         help="whether to cleanup old logfiles before starting")
 
-    log_url = CStr('', shortname='--log-url', config=True,
-        help="The ZMQ URL of the iplooger to aggregate logging.")
+    log_url = Unicode('', shortname='--log-url', config=True,
+        help="The ZMQ URL of the iplogger to aggregate logging.")
 
     config_file = Unicode(u'', config=True,
         help="""Path to ipcontroller configuration file.  The default is to use
diff --git a/IPython/parallel/apps/ipclusterapp.py b/IPython/parallel/apps/ipclusterapp.py
index 3257733..a70740d 100755
--- a/IPython/parallel/apps/ipclusterapp.py
+++ b/IPython/parallel/apps/ipclusterapp.py
@@ -29,7 +29,7 @@ from IPython.config.application import Application, boolean_flag
 from IPython.config.loader import Config
 from IPython.core.newapplication import BaseIPythonApplication
 from IPython.utils.importstring import import_item
-from IPython.utils.traitlets import Int, CStr, CUnicode, Str, Bool, CFloat, Dict, List
+from IPython.utils.traitlets import Int, Unicode, Bool, CFloat, Dict, List
 
 from IPython.parallel.apps.clusterdir import (
     ClusterApplication, ClusterDirError, ClusterDir,
@@ -285,7 +285,7 @@ class IPClusterEngines(ClusterApplication):
     n = Int(2, config=True,
         help="The number of engines to start.")
 
-    engine_launcher_class = Str('LocalEngineSetLauncher',
+    engine_launcher_class = Unicode('LocalEngineSetLauncher',
         config=True,
         help="The class for launching a set of Engines."
         )
@@ -420,7 +420,7 @@ class IPClusterStart(IPClusterEngines):
     delay = CFloat(1., config=True,
         help="delay (in s) between starting the controller and the engines")
 
-    controller_launcher_class = Str('LocalControllerLauncher',
+    controller_launcher_class = Unicode('LocalControllerLauncher',
         config=True,
         help="The class for launching a Controller."
         )
diff --git a/IPython/parallel/apps/ipcontrollerapp.py b/IPython/parallel/apps/ipcontrollerapp.py
index 3df9b1b..77cc47a 100755
--- a/IPython/parallel/apps/ipcontrollerapp.py
+++ b/IPython/parallel/apps/ipcontrollerapp.py
@@ -43,7 +43,7 @@ from IPython.parallel.apps.clusterdir import (
     # ClusterDirConfigLoader
 )
 from IPython.utils.importstring import import_item
-from IPython.utils.traitlets import Instance, Unicode, Bool, List, CStr, Dict
+from IPython.utils.traitlets import Instance, Unicode, Bool, List, Dict
 
 # from IPython.parallel.controller.controller import ControllerFactory
 from IPython.parallel.streamsession import StreamSession
@@ -139,7 +139,7 @@ class IPControllerApp(ClusterApplication):
 
     # internal
     children = List()
-    mq_class = CStr('zmq.devices.ProcessMonitoredQueue')
+    mq_class = Unicode('zmq.devices.ProcessMonitoredQueue')
 
     def _usethreads_changed(self, name, old, new):
         self.mq_class = 'zmq.devices.%sMonitoredQueue'%('Thread' if new else 'Process')
diff --git a/IPython/parallel/apps/ipengineapp.py b/IPython/parallel/apps/ipengineapp.py
index a31ad91..a545d42 100755
--- a/IPython/parallel/apps/ipengineapp.py
+++ b/IPython/parallel/apps/ipengineapp.py
@@ -37,7 +37,7 @@ from IPython.parallel.engine.streamkernel import Kernel
 from IPython.parallel.util import disambiguate_url
 
 from IPython.utils.importstring import import_item
-from IPython.utils.traitlets import Str, Bool, Unicode, Dict, List, CStr
+from IPython.utils.traitlets import Bool, Unicode, Dict, List, CStr
 
 
 #-----------------------------------------------------------------------------
@@ -78,7 +78,7 @@ mpi.size = 0
 
 class MPI(Configurable):
     """Configurable for MPI initialization"""
-    use = Str('', config=True,
+    use = Unicode('', config=True,
         help='How to enable MPI (mpi4py, pytrilinos, or empty string to disable).'
         )
 
@@ -87,7 +87,7 @@ class MPI(Configurable):
         if not self.init_script:
             self.init_script = self.default_inits.get(new, '')
 
-    init_script = Str('', config=True,
+    init_script = Unicode('', config=True,
         help="Initialization code for MPI")
 
     default_inits = Dict({'mpi4py' : mpi4py_init, 'pytrilinos':pytrilinos_init},
@@ -111,7 +111,7 @@ class IPEngineApp(ClusterApplication):
     
     startup_script = Unicode(u'', config=True,
         help='specify a script to be run at startup')
-    startup_command = Str('', config=True,
+    startup_command = Unicode('', config=True,
             help='specify a command to be run at startup')
 
     url_file = Unicode(u'', config=True,
diff --git a/IPython/parallel/apps/launcher.py b/IPython/parallel/apps/launcher.py
index 5dce600..42ad434 100644
--- a/IPython/parallel/apps/launcher.py
+++ b/IPython/parallel/apps/launcher.py
@@ -51,7 +51,7 @@ from zmq.eventloop import ioloop
 
 from IPython.external import Itpl
 # from IPython.config.configurable import Configurable
-from IPython.utils.traitlets import Any, Str, Int, List, Unicode, Dict, Instance, CUnicode
+from IPython.utils.traitlets import Any, Int, List, Unicode, Dict, Instance
 from IPython.utils.path import get_ipython_module_path
 from IPython.utils.process import find_cmd, pycmd2argv, FindCmdError
 
@@ -534,11 +534,11 @@ class SSHLauncher(LocalProcessLauncher):
         help="Program to launch via ssh")
     program_args = List([], config=True,
         help="args to pass to remote program")
-    hostname = CUnicode('', config=True,
+    hostname = Unicode('', config=True,
         help="hostname on which to launch the program")
-    user = CUnicode('', config=True,
+    user = Unicode('', config=True,
         help="username for ssh")
-    location = CUnicode('', config=True,
+    location = Unicode('', config=True,
         help="user@hostname location for ssh in one setting")
 
     def _hostname_changed(self, name, old, new):
@@ -647,18 +647,18 @@ def find_job_cmd():
 
 class WindowsHPCLauncher(BaseLauncher):
 
-    job_id_regexp = Str(r'\d+', config=True,
+    job_id_regexp = Unicode(r'\d+', config=True,
         help="""A regular expression used to get the job id from the output of the
         submit_command. """
         )
-    job_file_name = CUnicode(u'ipython_job.xml', config=True,
+    job_file_name = Unicode(u'ipython_job.xml', config=True,
         help="The filename of the instantiated job script.")
     # The full path to the instantiated job script. This gets made dynamically
     # by combining the work_dir with the job_file_name.
-    job_file = CUnicode(u'')
-    scheduler = CUnicode('', config=True,
+    job_file = Unicode(u'')
+    scheduler = Unicode('', config=True,
         help="The hostname of the scheduler to submit the job to.")
-    job_cmd = CUnicode(find_job_cmd(), config=True,
+    job_cmd = Unicode(find_job_cmd(), config=True,
         help="The command for submitting jobs.")
 
     def __init__(self, work_dir=u'.', config=None, **kwargs):
@@ -727,7 +727,7 @@ class WindowsHPCLauncher(BaseLauncher):
 
 class WindowsHPCControllerLauncher(WindowsHPCLauncher):
 
-    job_file_name = CUnicode(u'ipcontroller_job.xml', config=True,
+    job_file_name = Unicode(u'ipcontroller_job.xml', config=True,
         help="WinHPC xml job file.")
     extra_args = List([], config=False,
         help="extra args to pass to ipcontroller")
@@ -760,7 +760,7 @@ class WindowsHPCControllerLauncher(WindowsHPCLauncher):
 
 class WindowsHPCEngineSetLauncher(WindowsHPCLauncher):
 
-    job_file_name = CUnicode(u'ipengineset_job.xml', config=True,
+    job_file_name = Unicode(u'ipengineset_job.xml', config=True,
         help="jobfile for ipengines job")
     extra_args = List([], config=False,
         help="extra args to pas to ipengine")
@@ -815,29 +815,29 @@ class BatchSystemLauncher(BaseLauncher):
         help="The name of the command line program used to submit jobs.")
     delete_command = List([''], config=True,
         help="The name of the command line program used to delete jobs.")
-    job_id_regexp = CUnicode('', config=True,
+    job_id_regexp = Unicode('', config=True,
         help="""A regular expression used to get the job id from the output of the
         submit_command.""")
-    batch_template = CUnicode('', config=True,
+    batch_template = Unicode('', config=True,
         help="The string that is the batch script template itself.")
-    batch_template_file = CUnicode(u'', config=True,
+    batch_template_file = Unicode(u'', config=True,
         help="The file that contains the batch template.")
-    batch_file_name = CUnicode(u'batch_script', config=True,
+    batch_file_name = Unicode(u'batch_script', config=True,
         help="The filename of the instantiated batch script.")
-    queue = CUnicode(u'', config=True,
+    queue = Unicode(u'', config=True,
         help="The PBS Queue.")
     
     # not configurable, override in subclasses
     # PBS Job Array regex
-    job_array_regexp = CUnicode('')
-    job_array_template = CUnicode('')
+    job_array_regexp = Unicode('')
+    job_array_template = Unicode('')
     # PBS Queue regex
-    queue_regexp = CUnicode('')
-    queue_template = CUnicode('')
+    queue_regexp = Unicode('')
+    queue_template = Unicode('')
     # The default batch template, override in subclasses
-    default_template = CUnicode('')
+    default_template = Unicode('')
     # The full path to the instantiated batch script.
-    batch_file = CUnicode(u'')
+    batch_file = Unicode(u'')
     # the format dict used with batch_template:
     context = Dict()
 
@@ -924,22 +924,22 @@ class PBSLauncher(BatchSystemLauncher):
         help="The PBS submit command ['qsub']")
     delete_command = List(['qdel'], config=True,
         help="The PBS delete command ['qsub']")
-    job_id_regexp = CUnicode(r'\d+', config=True,
+    job_id_regexp = Unicode(r'\d+', config=True,
         help="Regular expresion for identifying the job ID [r'\d+']")
     
-    batch_file = CUnicode(u'')
-    job_array_regexp = CUnicode('#PBS\W+-t\W+[\w\d\-\$]+')
-    job_array_template = CUnicode('#PBS -t 1-$n')
-    queue_regexp = CUnicode('#PBS\W+-q\W+\$?\w+')
-    queue_template = CUnicode('#PBS -q $queue')
+    batch_file = Unicode(u'')
+    job_array_regexp = Unicode('#PBS\W+-t\W+[\w\d\-\$]+')
+    job_array_template = Unicode('#PBS -t 1-$n')
+    queue_regexp = Unicode('#PBS\W+-q\W+\$?\w+')
+    queue_template = Unicode('#PBS -q $queue')
 
 
 class PBSControllerLauncher(PBSLauncher):
     """Launch a controller using PBS."""
 
-    batch_file_name = CUnicode(u'pbs_controller', config=True,
+    batch_file_name = Unicode(u'pbs_controller', config=True,
         help="batch file name for the controller job.")
-    default_template= CUnicode("""#!/bin/sh
+    default_template= Unicode("""#!/bin/sh
 #PBS -V
 #PBS -N ipcontroller
 %s --log-to-file cluster_dir $cluster_dir
@@ -953,9 +953,9 @@ class PBSControllerLauncher(PBSLauncher):
 
 class PBSEngineSetLauncher(PBSLauncher):
     """Launch Engines using PBS"""
-    batch_file_name = CUnicode(u'pbs_engines', config=True,
+    batch_file_name = Unicode(u'pbs_engines', config=True,
         help="batch file name for the engine(s) job.")
-    default_template= CUnicode(u"""#!/bin/sh
+    default_template= Unicode(u"""#!/bin/sh
 #PBS -V
 #PBS -N ipengine
 %s cluster_dir $cluster_dir
@@ -970,17 +970,17 @@ class PBSEngineSetLauncher(PBSLauncher):
 
 class SGELauncher(PBSLauncher):
     """Sun GridEngine is a PBS clone with slightly different syntax"""
-    job_array_regexp = CUnicode('#$$\W+-t\W+[\w\d\-\$]+')
-    job_array_template = CUnicode('#$$ -t 1-$n')
-    queue_regexp = CUnicode('#$$\W+-q\W+\$?\w+')
-    queue_template = CUnicode('#$$ -q $queue')
+    job_array_regexp = Unicode('#$$\W+-t\W+[\w\d\-\$]+')
+    job_array_template = Unicode('#$$ -t 1-$n')
+    queue_regexp = Unicode('#$$\W+-q\W+\$?\w+')
+    queue_template = Unicode('#$$ -q $queue')
 
 class SGEControllerLauncher(SGELauncher):
     """Launch a controller using SGE."""
 
-    batch_file_name = CUnicode(u'sge_controller', config=True,
+    batch_file_name = Unicode(u'sge_controller', config=True,
         help="batch file name for the ipontroller job.")
-    default_template= CUnicode(u"""#$$ -V
+    default_template= Unicode(u"""#$$ -V
 #$$ -S /bin/sh
 #$$ -N ipcontroller
 %s --log-to-file cluster_dir=$cluster_dir
@@ -993,9 +993,9 @@ class SGEControllerLauncher(SGELauncher):
 
 class SGEEngineSetLauncher(SGELauncher):
     """Launch Engines with SGE"""
-    batch_file_name = CUnicode(u'sge_engines', config=True,
+    batch_file_name = Unicode(u'sge_engines', config=True,
         help="batch file name for the engine(s) job.")
-    default_template = CUnicode("""#$$ -V
+    default_template = Unicode("""#$$ -V
 #$$ -S /bin/sh
 #$$ -N ipengine
 %s cluster_dir=$cluster_dir
@@ -1020,7 +1020,7 @@ class IPClusterLauncher(LocalProcessLauncher):
     ipcluster_args = List(
         ['--clean-logs', '--log-to-file', 'log_level=%i'%logging.INFO], config=True,
         help="Command line arguments to pass to ipcluster.")
-    ipcluster_subcommand = Str('start')
+    ipcluster_subcommand = Unicode('start')
     ipcluster_n = Int(2)
 
     def find_args(self):
diff --git a/IPython/parallel/apps/logwatcher.py b/IPython/parallel/apps/logwatcher.py
index adf4355..32dbf7d 100644
--- a/IPython/parallel/apps/logwatcher.py
+++ b/IPython/parallel/apps/logwatcher.py
@@ -19,7 +19,7 @@ import sys
 import zmq
 from zmq.eventloop import ioloop, zmqstream
 
-from IPython.utils.traitlets import Int, Str, Instance, List
+from IPython.utils.traitlets import Int, Unicode, Instance, List
 
 from IPython.parallel.factory import LoggingFactory
 
@@ -36,7 +36,7 @@ class LogWatcher(LoggingFactory):
     """
     # configurables
     topics = List([''], config=True)
-    url = Str('tcp://127.0.0.1:20202', config=True)
+    url = Unicode('tcp://127.0.0.1:20202', config=True)
     
     # internals
     context = Instance(zmq.Context, (), {})
diff --git a/IPython/parallel/apps/winhpcjob.py b/IPython/parallel/apps/winhpcjob.py
index 492df58..7a39cb0 100644
--- a/IPython/parallel/apps/winhpcjob.py
+++ b/IPython/parallel/apps/winhpcjob.py
@@ -24,8 +24,8 @@ from xml.etree import ElementTree as ET
 
 from IPython.config.configurable import Configurable
 from IPython.utils.traitlets import (
-    Str, Int, List, Instance,
-    Enum, Bool, CStr
+    Unicode, Int, List, Instance,
+    Enum, Bool
 )
 
 #-----------------------------------------------------------------------------
@@ -74,27 +74,27 @@ def find_username():
 
 class WinHPCJob(Configurable):
 
-    job_id = Str('')
-    job_name = Str('MyJob', config=True)
+    job_id = Unicode('')
+    job_name = Unicode('MyJob', config=True)
     min_cores = Int(1, config=True)
     max_cores = Int(1, config=True)
     min_sockets = Int(1, config=True)
     max_sockets = Int(1, config=True)
     min_nodes = Int(1, config=True)
     max_nodes = Int(1, config=True)
-    unit_type = Str("Core", config=True)
+    unit_type = Unicode("Core", config=True)
     auto_calculate_min = Bool(True, config=True)
     auto_calculate_max = Bool(True, config=True)
     run_until_canceled = Bool(False, config=True)
     is_exclusive = Bool(False, config=True)
-    username = Str(find_username(), config=True)
-    job_type = Str('Batch', config=True)
+    username = Unicode(find_username(), config=True)
+    job_type = Unicode('Batch', config=True)
     priority = Enum(('Lowest','BelowNormal','Normal','AboveNormal','Highest'),
         default_value='Highest', config=True)
-    requested_nodes = Str('', config=True)
-    project = Str('IPython', config=True)
-    xmlns = Str('http://schemas.microsoft.com/HPCS2008/scheduler/')
-    version = Str("2.000")
+    requested_nodes = Unicode('', config=True)
+    project = Unicode('IPython', config=True)
+    xmlns = Unicode('http://schemas.microsoft.com/HPCS2008/scheduler/')
+    version = Unicode("2.000")
     tasks = List([])
 
     @property
@@ -165,21 +165,21 @@ class WinHPCJob(Configurable):
 
 class WinHPCTask(Configurable):
 
-    task_id = Str('')
-    task_name = Str('')
-    version = Str("2.000")
+    task_id = Unicode('')
+    task_name = Unicode('')
+    version = Unicode("2.000")
     min_cores = Int(1, config=True)
     max_cores = Int(1, config=True)
     min_sockets = Int(1, config=True)
     max_sockets = Int(1, config=True)
     min_nodes = Int(1, config=True)
     max_nodes = Int(1, config=True)
-    unit_type = Str("Core", config=True)
-    command_line = CStr('', config=True)
-    work_directory = CStr('', config=True)
+    unit_type = Unicode("Core", config=True)
+    command_line = Unicode('', config=True)
+    work_directory = Unicode('', config=True)
     is_rerunnaable = Bool(True, config=True)
-    std_out_file_path = CStr('', config=True)
-    std_err_file_path = CStr('', config=True)
+    std_out_file_path = Unicode('', config=True)
+    std_err_file_path = Unicode('', config=True)
     is_parametric = Bool(False, config=True)
     environment_variables = Instance(dict, args=(), config=True)
 
@@ -223,41 +223,41 @@ class WinHPCTask(Configurable):
 # By declaring these, we can configure the controller and engine separately!
 
 class IPControllerJob(WinHPCJob):
-    job_name = Str('IPController', config=False)
+    job_name = Unicode('IPController', config=False)
     is_exclusive = Bool(False, config=True)
-    username = Str(find_username(), config=True)
+    username = Unicode(find_username(), config=True)
     priority = Enum(('Lowest','BelowNormal','Normal','AboveNormal','Highest'),
         default_value='Highest', config=True)
-    requested_nodes = Str('', config=True)
-    project = Str('IPython', config=True)
+    requested_nodes = Unicode('', config=True)
+    project = Unicode('IPython', config=True)
 
 
 class IPEngineSetJob(WinHPCJob):
-    job_name = Str('IPEngineSet', config=False)
+    job_name = Unicode('IPEngineSet', config=False)
     is_exclusive = Bool(False, config=True)
-    username = Str(find_username(), config=True)
+    username = Unicode(find_username(), config=True)
     priority = Enum(('Lowest','BelowNormal','Normal','AboveNormal','Highest'),
         default_value='Highest', config=True)
-    requested_nodes = Str('', config=True)
-    project = Str('IPython', config=True)
+    requested_nodes = Unicode('', config=True)
+    project = Unicode('IPython', config=True)
 
 
 class IPControllerTask(WinHPCTask):
 
-    task_name = Str('IPController', config=True)
+    task_name = Unicode('IPController', config=True)
     controller_cmd = List(['ipcontroller.exe'], config=True)
     controller_args = List(['--log-to-file', '--log-level', '40'], config=True)
     # I don't want these to be configurable
-    std_out_file_path = CStr('', config=False)
-    std_err_file_path = CStr('', config=False)
+    std_out_file_path = Unicode('', config=False)
+    std_err_file_path = Unicode('', config=False)
     min_cores = Int(1, config=False)
     max_cores = Int(1, config=False)
     min_sockets = Int(1, config=False)
     max_sockets = Int(1, config=False)
     min_nodes = Int(1, config=False)
     max_nodes = Int(1, config=False)
-    unit_type = Str("Core", config=False)
-    work_directory = CStr('', config=False)
+    unit_type = Unicode("Core", config=False)
+    work_directory = Unicode('', config=False)
 
     def __init__(self, config=None):
         super(IPControllerTask, self).__init__(config=config)
@@ -272,20 +272,20 @@ class IPControllerTask(WinHPCTask):
 
 class IPEngineTask(WinHPCTask):
 
-    task_name = Str('IPEngine', config=True)
+    task_name = Unicode('IPEngine', config=True)
     engine_cmd = List(['ipengine.exe'], config=True)
     engine_args = List(['--log-to-file', '--log-level', '40'], config=True)
     # I don't want these to be configurable
-    std_out_file_path = CStr('', config=False)
-    std_err_file_path = CStr('', config=False)
+    std_out_file_path = Unicode('', config=False)
+    std_err_file_path = Unicode('', config=False)
     min_cores = Int(1, config=False)
     max_cores = Int(1, config=False)
     min_sockets = Int(1, config=False)
     max_sockets = Int(1, config=False)
     min_nodes = Int(1, config=False)
     max_nodes = Int(1, config=False)
-    unit_type = Str("Core", config=False)
-    work_directory = CStr('', config=False)
+    unit_type = Unicode("Core", config=False)
+    work_directory = Unicode('', config=False)
 
     def __init__(self, config=None):
         super(IPEngineTask,self).__init__(config=config)
diff --git a/IPython/parallel/client/client.py b/IPython/parallel/client/client.py
index 329f535..1984ba6 100644
--- a/IPython/parallel/client/client.py
+++ b/IPython/parallel/client/client.py
@@ -24,8 +24,8 @@ import zmq
 # from zmq.eventloop import ioloop, zmqstream
 
 from IPython.utils.path import get_ipython_dir
-from IPython.utils.traitlets import (HasTraits, Int, Instance, CUnicode, 
-                                    Dict, List, Bool, Str, Set)
+from IPython.utils.traitlets import (HasTraits, Int, Instance, Unicode,
+                                    Dict, List, Bool, Set)
 from IPython.external.decorator import decorator
 from IPython.external.ssh import tunnel
 
@@ -213,7 +213,7 @@ class Client(HasTraits):
     metadata = Instance('collections.defaultdict', (Metadata,))
     history = List()
     debug = Bool(False)
-    profile=CUnicode('default')
+    profile=Unicode('default')
     
     _outstanding_dict = Instance('collections.defaultdict', (set,))
     _ids = List()
@@ -229,7 +229,7 @@ class Client(HasTraits):
     _notification_socket=Instance('zmq.Socket')
     _mux_socket=Instance('zmq.Socket')
     _task_socket=Instance('zmq.Socket')
-    _task_scheme=Str()
+    _task_scheme=Unicode()
     _closed = False
     _ignored_control_replies=Int(0)
     _ignored_hub_replies=Int(0)
diff --git a/IPython/parallel/controller/dictdb.py b/IPython/parallel/controller/dictdb.py
index 0526f2d..05f20ad 100644
--- a/IPython/parallel/controller/dictdb.py
+++ b/IPython/parallel/controller/dictdb.py
@@ -46,7 +46,7 @@ from datetime import datetime
 
 from IPython.config.configurable import Configurable
 
-from IPython.utils.traitlets import Dict, CUnicode
+from IPython.utils.traitlets import Dict, Unicode
 
 filters = {
  '$lt' : lambda a,b: a < b,
@@ -82,7 +82,7 @@ class CompositeFilter(object):
 class BaseDB(Configurable):
     """Empty Parent class so traitlets work on DB."""
     # base configurable traits:
-    session = CUnicode("")
+    session = Unicode("")
 
 class DictDB(BaseDB):
     """Basic in-memory dict-based object for saving Task Records.
diff --git a/IPython/parallel/controller/heartmonitor.py b/IPython/parallel/controller/heartmonitor.py
index cee6467..bd69d9a 100644
--- a/IPython/parallel/controller/heartmonitor.py
+++ b/IPython/parallel/controller/heartmonitor.py
@@ -15,10 +15,10 @@ import time
 import uuid
 
 import zmq
-from zmq.devices import ProcessDevice, ThreadDevice
+from zmq.devices import ThreadDevice
 from zmq.eventloop import ioloop, zmqstream
 
-from IPython.utils.traitlets import Set, Instance, CFloat, Bool, CStr
+from IPython.utils.traitlets import Set, Instance, CFloat
 from IPython.parallel.factory import LoggingFactory
 
 class Heart(object):
diff --git a/IPython/parallel/controller/hub.py b/IPython/parallel/controller/hub.py
index 1477da8..5b3bdaa 100755
--- a/IPython/parallel/controller/hub.py
+++ b/IPython/parallel/controller/hub.py
@@ -26,7 +26,7 @@ from zmq.eventloop.zmqstream import ZMQStream
 # internal:
 from IPython.utils.importstring import import_item
 from IPython.utils.traitlets import (
-        HasTraits, Instance, Int, CStr, Str, Dict, Set, List, Bool, Tuple
+        HasTraits, Instance, Int, Unicode, Dict, Set, Tuple, CStr
         )
 
 from IPython.parallel import error, util
@@ -105,10 +105,10 @@ class EngineConnector(HasTraits):
     heartbeat (str): identity of heartbeat XREQ socket
     """
     id=Int(0)
-    queue=Str()
-    control=Str()
-    registration=Str()
-    heartbeat=Str()
+    queue=CStr()
+    control=CStr()
+    registration=CStr()
+    heartbeat=CStr()
     pending=Set()
 
 class HubFactory(RegistrationFactory):
@@ -156,24 +156,24 @@ class HubFactory(RegistrationFactory):
     def _notifier_port_default(self):
         return util.select_random_ports(1)[0]
     
-    engine_ip = CStr('127.0.0.1', config=True,
+    engine_ip = Unicode('127.0.0.1', config=True,
         help="IP on which to listen for engine connections. [default: loopback]")
-    engine_transport = CStr('tcp', config=True,
+    engine_transport = Unicode('tcp', config=True,
         help="0MQ transport for engine connections. [default: tcp]")
     
-    client_ip = CStr('127.0.0.1', config=True,
+    client_ip = Unicode('127.0.0.1', config=True,
         help="IP on which to listen for client connections. [default: loopback]")
-    client_transport = CStr('tcp', config=True,
+    client_transport = Unicode('tcp', config=True,
         help="0MQ transport for client connections. [default : tcp]")
     
-    monitor_ip = CStr('127.0.0.1', config=True,
+    monitor_ip = Unicode('127.0.0.1', config=True,
         help="IP on which to listen for monitor messages. [default: loopback]")
-    monitor_transport = CStr('tcp', config=True,
+    monitor_transport = Unicode('tcp', config=True,
         help="0MQ transport for monitor messages. [default : tcp]")
     
-    monitor_url = CStr('')
+    monitor_url = Unicode('')
     
-    db_class = CStr('IPython.parallel.controller.dictdb.DictDB', config=True,
+    db_class = Unicode('IPython.parallel.controller.dictdb.DictDB', config=True,
         help="""The class to use for the DB backend""")
     
     # not configurable
@@ -253,7 +253,7 @@ class HubFactory(RegistrationFactory):
         # connect the db
         self.log.info('Hub using DB backend: %r'%(self.db_class.split()[-1]))
         # cdir = self.config.Global.cluster_dir
-        self.db = import_item(self.db_class)(session=self.session.session, config=self.config)
+        self.db = import_item(str(self.db_class))(session=self.session.session, config=self.config)
         time.sleep(.25)
         try:
             scheme = self.config.TaskScheduler.scheme_name
diff --git a/IPython/parallel/controller/mongodb.py b/IPython/parallel/controller/mongodb.py
index 0ecc16c..cb8d4fb 100644
--- a/IPython/parallel/controller/mongodb.py
+++ b/IPython/parallel/controller/mongodb.py
@@ -9,7 +9,7 @@
 from pymongo import Connection
 from pymongo.binary import Binary
 
-from IPython.utils.traitlets import Dict, List, CUnicode, CStr, Instance
+from IPython.utils.traitlets import Dict, List, Unicode, Instance
 
 from .dictdb import BaseDB
 
@@ -29,7 +29,7 @@ class MongoDB(BaseDB):
         necessary if the default mongodb configuration does not point to your
         mongod instance."""
     )
-    database = CUnicode(config=True,
+    database = Unicode(config=True,
         help="""The MongoDB database name to use for storing tasks for this session. If unspecified,
         a new database will be created with the Hub's IDENT.  Specifying the database will result
         in tasks from previous sessions being available via Clients' db_query and
diff --git a/IPython/parallel/controller/sqlitedb.py b/IPython/parallel/controller/sqlitedb.py
index 26f1ce8..737cf2d 100644
--- a/IPython/parallel/controller/sqlitedb.py
+++ b/IPython/parallel/controller/sqlitedb.py
@@ -15,7 +15,7 @@ import sqlite3
 
 from zmq.eventloop import ioloop
 
-from IPython.utils.traitlets import CUnicode, CStr, Instance, List
+from IPython.utils.traitlets import Unicode, Instance, List
 from .dictdb import BaseDB
 from IPython.parallel.util import ISO8601
 
@@ -83,12 +83,12 @@ def _convert_bufs(bs):
 class SQLiteDB(BaseDB):
     """SQLite3 TaskRecord backend."""
     
-    filename = CUnicode('tasks.db', config=True,
+    filename = Unicode('tasks.db', config=True,
         help="""The filename of the sqlite task database. [default: 'tasks.db']""")
-    location = CUnicode('', config=True,
+    location = Unicode('', config=True,
         help="""The directory containing the sqlite task database.  The default
         is to use the cluster_dir location.""")
-    table = CUnicode("", config=True,
+    table = Unicode("", config=True,
         help="""The SQLite Table to use for storing tasks for this session. If unspecified,
         a new table will be created with the Hub's IDENT.  Specifying the table will result
         in tasks from previous sessions being available via Clients' db_query and
diff --git a/IPython/parallel/engine/engine.py b/IPython/parallel/engine/engine.py
index c7dc6e2..891f31a 100755
--- a/IPython/parallel/engine/engine.py
+++ b/IPython/parallel/engine/engine.py
@@ -19,7 +19,7 @@ import zmq
 from zmq.eventloop import ioloop, zmqstream
 
 # internal
-from IPython.utils.traitlets import Instance, Str, Dict, Int, Type, CFloat
+from IPython.utils.traitlets import Instance, Dict, Int, Type, CFloat, Unicode
 # from IPython.utils.localinterfaces import LOCALHOST 
 
 from IPython.parallel.controller.heartmonitor import Heart
@@ -39,7 +39,7 @@ class EngineFactory(RegistrationFactory):
     display_hook_factory=Type('IPython.zmq.displayhook.DisplayHook', config=True,
         help="""The class for handling displayhook.
         Typically 'IPython.zmq.displayhook.DisplayHook'""")
-    location=Str(config=True,
+    location=Unicode(config=True,
         help="""The location (an IP address) of the controller.  This is
         used for disambiguating URLs, to determine whether
         loopback should be used to connect or the public address.""")
diff --git a/IPython/parallel/engine/streamkernel.py b/IPython/parallel/engine/streamkernel.py
index 668bba7..8ea1e7f 100755
--- a/IPython/parallel/engine/streamkernel.py
+++ b/IPython/parallel/engine/streamkernel.py
@@ -28,7 +28,7 @@ import zmq
 from zmq.eventloop import ioloop, zmqstream
 
 # Local imports.
-from IPython.utils.traitlets import Instance, List, Int, Dict, Set, Str, CStr
+from IPython.utils.traitlets import Instance, List, Int, Dict, Set, Unicode
 from IPython.zmq.completer import KernelCompleter
 
 from IPython.parallel.error import wrap_exception
@@ -64,7 +64,7 @@ class Kernel(SessionFactory):
     #---------------------------------------------------------------------------
     
     # kwargs:
-    exec_lines = List(CStr, config=True,
+    exec_lines = List(Unicode, config=True,
         help="List of lines to execute")
 
     int_id = Int(-1)
diff --git a/IPython/parallel/factory.py b/IPython/parallel/factory.py
index 593ff56..1fb9998 100644
--- a/IPython/parallel/factory.py
+++ b/IPython/parallel/factory.py
@@ -18,7 +18,7 @@ import os
 from zmq.eventloop.ioloop import IOLoop
 
 from IPython.config.configurable import Configurable
-from IPython.utils.traitlets import Str,Int,Instance, CUnicode, CStr
+from IPython.utils.traitlets import Int, Instance, Unicode
 
 import IPython.parallel.streamsession as ss
 from IPython.parallel.util import select_random_ports
@@ -29,7 +29,7 @@ from IPython.parallel.util import select_random_ports
 class LoggingFactory(Configurable):
     """A most basic class, that has a `log` (type:`Logger`) attribute, set via a `logname` Trait."""
     log = Instance('logging.Logger', ('ZMQ', logging.WARN))
-    logname = CUnicode('ZMQ')
+    logname = Unicode('ZMQ')
     def _logname_changed(self, name, old, new):
         self.log = logging.getLogger(new)
     
@@ -55,14 +55,14 @@ class SessionFactory(LoggingFactory):
 class RegistrationFactory(SessionFactory):
     """The Base Configurable for objects that involve registration."""
     
-    url = Str('', config=True,
+    url = Unicode('', config=True,
         help="""The 0MQ url used for registration. This sets transport, ip, and port
         in one variable. For example: url='tcp://127.0.0.1:12345' or
         url='epgm://*:90210'""") # url takes precedence over ip,regport,transport
-    transport = Str('tcp', config=True,
+    transport = Unicode('tcp', config=True,
         help="""The 0MQ transport for communications.  This will likely be
         the default of 'tcp', but other values include 'ipc', 'epgm', 'inproc'.""")
-    ip = Str('127.0.0.1', config=True,
+    ip = Unicode('127.0.0.1', config=True,
         help="""The IP address for registration.  This is generally either
         '127.0.0.1' for loopback only or '*' for all interfaces.
         [default: '127.0.0.1']""")
diff --git a/IPython/parallel/streamsession.py b/IPython/parallel/streamsession.py
index 5c32313..96e4955 100644
--- a/IPython/parallel/streamsession.py
+++ b/IPython/parallel/streamsession.py
@@ -27,7 +27,7 @@ from zmq.eventloop.zmqstream import ZMQStream
 
 from IPython.config.configurable import Configurable
 from IPython.utils.importstring import import_item
-from IPython.utils.traitlets import Str, CStr, CUnicode, Bool, Any
+from IPython.utils.traitlets import CStr, Unicode, Bool, Any
 
 from .util import ISO8601
 
@@ -121,7 +121,7 @@ def extract_header(msg_or_header):
 class StreamSession(Configurable):
     """tweaked version of IPython.zmq.session.Session, for development in Parallel"""
     debug=Bool(False, config=True, help="""Debug output in the StreamSession""")
-    packer = Str('json',config=True,
+    packer = Unicode('json',config=True,
             help="""The name of the packer for serializing messages.
             Should be one of 'json', 'pickle', or an import name
             for a custom serializer.""")
@@ -135,7 +135,7 @@ class StreamSession(Configurable):
         else:
             self.pack = import_item(new)
 
-    unpacker = Str('json',config=True,
+    unpacker = Unicode('json',config=True,
         help="""The name of the unpacker for unserializing messages.
         Only used with custom functions for `packer`.""")
     def _unpacker_changed(self, name, old, new):
@@ -151,13 +151,13 @@ class StreamSession(Configurable):
     session = CStr('',config=True,
         help="""The UUID identifying this session.""")
     def _session_default(self):
-        return str(uuid.uuid4())
-    username = CUnicode(os.environ.get('USER','username'),config=True,
+        return bytes(uuid.uuid4())
+    username = Unicode(os.environ.get('USER','username'),config=True,
         help="""Username for the Session. Default is your system username.""")
     key = CStr('', config=True,
         help="""execution key, for extra authentication.""")
 
-    keyfile = CUnicode('', config=True,
+    keyfile = Unicode('', config=True,
         help="""path to file containing execution key.""")
     def _keyfile_changed(self, name, old, new):
         with open(new, 'rb') as f: