diff --git a/test/py/RunClientServer.py b/test/py/RunClientServer.py
index 7224bac..fa2a264 100755
--- a/test/py/RunClientServer.py
+++ b/test/py/RunClientServer.py
@@ -21,108 +21,92 @@
 
 from __future__ import division
 from __future__ import print_function
-import time
+import copy
+import glob
+import os
+import signal
 import socket
 import subprocess
 import sys
-import os
-import signal
+import time
 from optparse import OptionParser
 
-parser = OptionParser()
-parser.add_option('--genpydirs', type='string', dest='genpydirs',
-    default='default,slots,newstyle,newstyleslots,dynamic,dynamicslots',
-    help='directory extensions for generated code, used as suffixes for \"gen-py-*\" added sys.path for individual tests')
-parser.add_option("--port", type="int", dest="port", default=9090,
-    help="port number for server to listen on")
-parser.add_option('-v', '--verbose', action="store_const",
-    dest="verbose", const=2,
-    help="verbose output")
-parser.add_option('-q', '--quiet', action="store_const",
-    dest="verbose", const=0,
-    help="minimal output")
-parser.set_defaults(verbose=1)
-options, args = parser.parse_args()
+SCRIPT_DIR = os.path.abspath(os.path.dirname(__file__))
+ROOT_DIR = os.path.dirname(os.path.dirname(SCRIPT_DIR))
+DEFAULT_LIBDIR_GLOB = os.path.join(ROOT_DIR, 'lib', 'py', 'build', 'lib.*')
+DEFAULT_LIBDIR_PY3 = os.path.join(ROOT_DIR, 'lib', 'py', 'build', 'lib')
 
-generated_dirs = []
-for gp_dir in options.genpydirs.split(','):
-  generated_dirs.append('gen-py-%s' % (gp_dir))
-
-SCRIPTS = ['TSimpleJSONProtocolTest.py',
-           'SerializationTest.py',
-           'TestEof.py',
-           'TestSyntax.py',
-           'TestSocket.py']
+SCRIPTS = [
+  'TSimpleJSONProtocolTest.py',
+  'SerializationTest.py',
+  'TestEof.py',
+  'TestSyntax.py',
+  'TestSocket.py',
+]
 FRAMED = ["TNonblockingServer"]
 SKIP_ZLIB = ['TNonblockingServer', 'THttpServer']
 SKIP_SSL = ['TNonblockingServer', 'THttpServer']
 EXTRA_DELAY = dict(TProcessPoolServer=5.5)
 
-PROTOS= [
-    'accel',
-    'binary',
-    'compact',
-    'json']
+PROTOS = [
+  'accel',
+  'binary',
+  'compact',
+  'json',
+]
 
 SERVERS = [
   "TSimpleServer",
   "TThreadedServer",
   "TThreadPoolServer",
-  "TProcessPoolServer", # new!
+  "TProcessPoolServer",
   "TForkingServer",
   "TNonblockingServer",
-  "THttpServer" ]
-
-# Test for presence of multiprocessing module, and if it is not present, then
-# remove it from the list of available servers.
-try:
-  import multiprocessing
-except:
-  print('Warning: the multiprocessing module is unavailable. Skipping tests for TProcessPoolServer')
-  SERVERS.remove('TProcessPoolServer')
-
-try:
-  import ssl
-except:
-  print('Warning, no ssl module available. Skipping all SSL tests.')
-  SKIP_SSL.extend(SERVERS)
-
-# commandline permits a single class name to be specified to override SERVERS=[...]
-if len(args) == 1:
-  if args[0] in SERVERS:
-    SERVERS = args
-  else:
-    print('Unavailable server type "%s", please choose one of: %s' % (args[0], SERVERS))
-    sys.exit(0)
+  "THttpServer",
+]
 
 
 def relfile(fname):
-    return os.path.join(os.path.dirname(__file__), fname)
+    return os.path.join(SCRIPT_DIR, fname)
 
-def runScriptTest(genpydir, script):
-  script_args = [sys.executable, relfile(script) ]
-  script_args.append('--genpydir=%s' % genpydir)
-  serverproc = subprocess.Popen(script_args)
+
+def setup_pypath(dirs):
+  env = copy.copy(os.environ)
+  pypath = env.get('PYTHONPATH', None)
+  if pypath:
+    dirs.append(pypath)
+  env['PYTHONPATH'] = ':'.join(dirs)
+  return env
+
+
+def runScriptTest(libdir, genpydir, script):
+  env = setup_pypath([libdir, genpydir])
+  script_args = [sys.executable, relfile(script)]
   print('\nTesting script: %s\n----' % (' '.join(script_args)))
-  ret = subprocess.call(script_args)
+  ret = subprocess.call(script_args, env=env)
   if ret != 0:
+    print('*** FAILED ***', file=sys.stderr)
+    print('LIBDIR: %s' % libdir, file=sys.stderr)
+    print('PY_GEN: %s' % genpydir, file=sys.stderr)
+    print('SCRIPT: %s' % script, file=sys.stderr)
     raise Exception("Script subprocess failed, retcode=%d, args: %s" % (ret, ' '.join(script_args)))
 
-def runServiceTest(genpydir, server_class, proto, port, use_zlib, use_ssl):
+
+def runServiceTest(libdir, genpydir, server_class, proto, port, use_zlib, use_ssl, verbose):
+  env = setup_pypath([libdir, genpydir])
   # Build command line arguments
-  server_args = [sys.executable, relfile('TestServer.py') ]
-  cli_args = [sys.executable, relfile('TestClient.py') ]
+  server_args = [sys.executable, relfile('TestServer.py')]
+  cli_args = [sys.executable, relfile('TestClient.py')]
   for which in (server_args, cli_args):
-    which.append('--genpydir=%s' % genpydir)
-    which.append('--protocol=%s' % proto) # accel, binary or compact
-    which.append('--port=%d' % port) # default to 9090
+    which.append('--protocol=%s' % proto)  # accel, binary, compact or json
+    which.append('--port=%d' % port)  # default to 9090
     if use_zlib:
       which.append('--zlib')
     if use_ssl:
       which.append('--ssl')
-    if options.verbose == 0:
+    if verbose == 0:
       which.append('-q')
-    if options.verbose == 2:
+    if verbose == 2:
       which.append('-v')
   # server-specific option to select server class
   server_args.append(server_class)
@@ -133,14 +117,14 @@
      cli_args.append('--transport=buffered')
   if server_class == 'THttpServer':
     cli_args.append('--http=/')
-  if options.verbose > 0:
+  if verbose > 0:
     print('Testing server %s: %s' % (server_class, ' '.join(server_args)))
-  serverproc = subprocess.Popen(server_args)
+  serverproc = subprocess.Popen(server_args, env=env)
 
   def ensureServerAlive():
     if serverproc.poll() is not None:
       print(('FAIL: Server process (%s) failed with retcode %d')
-             % (' '.join(server_args), serverproc.returncode))
+            % (' '.join(server_args), serverproc.returncode))
       raise Exception('Server subprocess %s died, args: %s'
                       % (server_class, ' '.join(server_args)))
 
@@ -161,55 +145,166 @@
     sock.close()
 
   try:
-    if options.verbose > 0:
+    if verbose > 0:
       print('Testing client: %s' % (' '.join(cli_args)))
-    ret = subprocess.call(cli_args)
+    ret = subprocess.call(cli_args, env=env)
     if ret != 0:
+      print('*** FAILED ***', file=sys.stderr)
+      print('LIBDIR: %s' % libdir, file=sys.stderr)
+      print('PY_GEN: %s' % genpydir, file=sys.stderr)
       raise Exception("Client subprocess failed, retcode=%d, args: %s" % (ret, ' '.join(cli_args)))
   finally:
     # check that server didn't die
     ensureServerAlive()
     extra_sleep = EXTRA_DELAY.get(server_class, 0)
-    if extra_sleep > 0 and options.verbose > 0:
+    if extra_sleep > 0 and verbose > 0:
       print('Giving %s (proto=%s,zlib=%s,ssl=%s) an extra %d seconds for child'
-             'processes to terminate via alarm'
-             % (server_class, proto, use_zlib, use_ssl, extra_sleep))
+            'processes to terminate via alarm'
+            % (server_class, proto, use_zlib, use_ssl, extra_sleep))
       time.sleep(extra_sleep)
     os.kill(serverproc.pid, signal.SIGKILL)
     serverproc.wait()
 
-test_count = 0
-# run tests without a client/server first
-print('----------------')
-print(' Executing individual test scripts with various generated code directories')
-print(' Directories to be tested: ' + ', '.join(generated_dirs))
-print(' Scripts to be tested: ' + ', '.join(SCRIPTS))
-print('----------------')
-for genpydir in generated_dirs:
-  for script in SCRIPTS:
-    runScriptTest(genpydir, script)
 
-print('----------------')
-print(' Executing Client/Server tests with various generated code directories')
-print(' Servers to be tested: ' + ', '.join(SERVERS))
-print(' Directories to be tested: ' + ', '.join(generated_dirs))
-print(' Protocols to be tested: ' + ', '.join(PROTOS))
-print(' Options to be tested: ZLIB(yes/no), SSL(yes/no)')
-print('----------------')
-for try_server in SERVERS:
+class TestCases(object):
+  def __init__(self, libdir, port, gendirs, servers, verbose):
+    self.libdir = libdir
+    self.port = port
+    self.verbose = verbose
+    self.gendirs = gendirs
+    self.servers = servers
+
+  def default_conf(self):
+    return {
+      'gendir': self.gendirs[0],
+      'server': self.servers[0],
+      'proto': PROTOS[0],
+      'zlib': False,
+      'ssl': False,
+    }
+
+  def run(self, conf, test_count):
+    with_zlib = conf['zlib']
+    with_ssl = conf['ssl']
+    try_server = conf['server']
+    try_proto = conf['proto']
+    genpydir = conf['gendir']
+    # skip any servers that don't work with the Zlib transport
+    if with_zlib and try_server in SKIP_ZLIB:
+      return False
+    # skip any servers that don't work with SSL
+    if with_ssl and try_server in SKIP_SSL:
+      return False
+    if self.verbose > 0:
+      print('\nTest run #%d:  (includes %s) Server=%s,  Proto=%s,  zlib=%s,  SSL=%s'
+            % (test_count, genpydir, try_server, try_proto, with_zlib, with_ssl))
+    runServiceTest(self.libdir, genpydir, try_server, try_proto, self.port, with_zlib, with_ssl, self.verbose)
+    if self.verbose > 0:
+      print('OK: Finished (includes %s)  %s / %s proto / zlib=%s / SSL=%s.   %d combinations tested.'
+            % (genpydir, try_server, try_proto, with_zlib, with_ssl, test_count))
+    return True
+
+  def test_feature(self, name, values):
+    test_count = 0
+    conf = self.default_conf()
+    for try_server in values:
+      conf[name] = try_server
+      if self.run(conf, test_count):
+        test_count += 1
+    return test_count
+
+  def run_all_tests(self):
+    test_count = 0
+    for try_server in self.servers:
+      for genpydir in self.gendirs:
+        for try_proto in PROTOS:
+          for with_zlib in (False, True):
+            # skip any servers that don't work with the Zlib transport
+            if with_zlib and try_server in SKIP_ZLIB:
+              continue
+            for with_ssl in (False, True):
+              # skip any servers that don't work with SSL
+              if with_ssl and try_server in SKIP_SSL:
+                continue
+              test_count += 1
+              if self.verbose > 0:
+                print('\nTest run #%d:  (includes %s) Server=%s,  Proto=%s,  zlib=%s,  SSL=%s'
+                      % (test_count, genpydir, try_server, try_proto, with_zlib, with_ssl))
+              runServiceTest(self.libdir, genpydir, try_server, try_proto, self.port, with_zlib, with_ssl)
+              if self.verbose > 0:
+                print('OK: Finished (includes %s)  %s / %s proto / zlib=%s / SSL=%s.   %d combinations tested.'
+                      % (genpydir, try_server, try_proto, with_zlib, with_ssl, test_count))
+    return test_count
+
+
+def default_libdir():
+  if sys.version_info[0] == 2:
+    return glob.glob(DEFAULT_LIBDIR_GLOB)[0]
+  else:
+    return DEFAULT_LIBDIR_PY3
+
+
+def main():
+  parser = OptionParser()
+  parser.add_option('--all', action="store_true", dest='all')
+  parser.add_option('--genpydirs', type='string', dest='genpydirs',
+                    default='default,slots,newstyle,newstyleslots,dynamic,dynamicslots',
+                    help='directory extensions for generated code, used as suffixes for \"gen-py-*\" added sys.path for individual tests')
+  parser.add_option("--port", type="int", dest="port", default=9090,
+                    help="port number for server to listen on")
+  parser.add_option('-v', '--verbose', action="store_const",
+                    dest="verbose", const=2,
+                    help="verbose output")
+  parser.add_option('-q', '--quiet', action="store_const",
+                    dest="verbose", const=0,
+                    help="minimal output")
+  parser.add_option('-L', '--libdir', dest="libdir", default=default_libdir(),
+                    help="directory path that contains Thrift Python library")
+  parser.set_defaults(verbose=1)
+  options, args = parser.parse_args()
+
+  generated_dirs = []
+  for gp_dir in options.genpydirs.split(','):
+    generated_dirs.append('gen-py-%s' % (gp_dir))
+
+  # commandline permits a single class name to be specified to override SERVERS=[...]
+  servers = SERVERS
+  if len(args) == 1:
+    if args[0] in SERVERS:
+      servers = args
+    else:
+      print('Unavailable server type "%s", please choose one of: %s' % (args[0], servers))
+      sys.exit(0)
+
+  tests = TestCases(options.libdir, options.port, generated_dirs, servers, options.verbose)
+
+  # run tests without a client/server first
+  print('----------------')
+  print(' Executing individual test scripts with various generated code directories')
+  print(' Directories to be tested: ' + ', '.join(generated_dirs))
+  print(' Scripts to be tested: ' + ', '.join(SCRIPTS))
+  print('----------------')
   for genpydir in generated_dirs:
-    for try_proto in PROTOS:
-      for with_zlib in (False, True):
-        # skip any servers that don't work with the Zlib transport
-        if with_zlib and try_server in SKIP_ZLIB:
-          continue
-        for with_ssl in (False, True):
-          # skip any servers that don't work with SSL
-          if with_ssl and try_server in SKIP_SSL:
-            continue
-          test_count += 1
-          if options.verbose > 0:
-            print('\nTest run #%d:  (includes %s) Server=%s,  Proto=%s,  zlib=%s,  SSL=%s' % (test_count, genpydir, try_server, try_proto, with_zlib, with_ssl))
-          runServiceTest(genpydir, try_server, try_proto, options.port, with_zlib, with_ssl)
-          if options.verbose > 0:
-            print('OK: Finished (includes %s)  %s / %s proto / zlib=%s / SSL=%s.   %d combinations tested.' % (genpydir, try_server, try_proto, with_zlib, with_ssl, test_count))
+    for script in SCRIPTS:
+      runScriptTest(options.libdir, genpydir, script)
+
+  print('----------------')
+  print(' Executing Client/Server tests with various generated code directories')
+  print(' Servers to be tested: ' + ', '.join(servers))
+  print(' Directories to be tested: ' + ', '.join(generated_dirs))
+  print(' Protocols to be tested: ' + ', '.join(PROTOS))
+  print(' Options to be tested: ZLIB(yes/no), SSL(yes/no)')
+  print('----------------')
+
+  if options.all:
+    tests.run_all_tests()
+  else:
+    tests.test_feature('gendir', generated_dirs)
+    tests.test_feature('server', servers)
+    tests.test_feature('proto', PROTOS)
+    tests.test_feature('zlib', [False, True])
+    tests.test_feature('ssl', [False, True])
+
+
+if __name__ == '__main__':
+  sys.exit(main())