diff --git a/Lib/distutils/spawn.py b/Lib/distutils/spawn.py
index 8c476dc..2b62c96 100644
--- a/Lib/distutils/spawn.py
+++ b/Lib/distutils/spawn.py
@@ -96,15 +96,42 @@
             raise DistutilsExecError(
                   "command '%s' failed with exit status %d" % (cmd[0], rc))
 
+if sys.platform == 'darwin':
+    from distutils import sysconfig
+    _cfg_target = None
+    _cfg_target_split = None
+
 def _spawn_posix(cmd, search_path=1, verbose=0, dry_run=0):
     log.info(' '.join(cmd))
     if dry_run:
         return
     exec_fn = search_path and os.execvp or os.execv
+    exec_args = [cmd[0], cmd]
+    if sys.platform == 'darwin':
+        global _cfg_target, _cfg_target_split
+        if _cfg_target is None:
+            _cfg_target = sysconfig.get_config_var(
+                                  'MACOSX_DEPLOYMENT_TARGET') or ''
+            if _cfg_target:
+                _cfg_target_split = [int(x) for x in _cfg_target.split('.')]
+        if _cfg_target:
+            # ensure that the deployment target of build process is not less
+            # than that used when the interpreter was built. This ensures
+            # extension modules are built with correct compatibility values
+            cur_target = os.environ.get('MACOSX_DEPLOYMENT_TARGET', _cfg_target)
+            if _cfg_target_split > [int(x) for x in cur_target.split('.')]:
+                my_msg = ('$MACOSX_DEPLOYMENT_TARGET mismatch: '
+                          'now "%s" but "%s" during configure'
+                                % (cur_target, _cfg_target))
+                raise DistutilsPlatformError(my_msg)
+            env = dict(os.environ,
+                       MACOSX_DEPLOYMENT_TARGET=cur_target)
+            exec_fn = search_path and os.execvpe or os.execve
+            exec_args.append(env)
     pid = os.fork()
     if pid == 0: # in the child
         try:
-            exec_fn(cmd[0], cmd)
+            exec_fn(*exec_args)
         except OSError as e:
             sys.stderr.write("unable to execute %s: %s\n"
                              % (cmd[0], e.strerror))
diff --git a/Lib/distutils/sysconfig.py b/Lib/distutils/sysconfig.py
index 06bbc01..9d7d190 100644
--- a/Lib/distutils/sysconfig.py
+++ b/Lib/distutils/sysconfig.py
@@ -419,21 +419,6 @@
 
         raise DistutilsPlatformError(my_msg)
 
-    # On MacOSX we need to check the setting of the environment variable
-    # MACOSX_DEPLOYMENT_TARGET: configure bases some choices on it so
-    # it needs to be compatible.
-    # If it isn't set we set it to the configure-time value
-    if sys.platform == 'darwin' and 'MACOSX_DEPLOYMENT_TARGET' in g:
-        cfg_target = g['MACOSX_DEPLOYMENT_TARGET']
-        cur_target = os.getenv('MACOSX_DEPLOYMENT_TARGET', '')
-        if cur_target == '':
-            cur_target = cfg_target
-            os.environ['MACOSX_DEPLOYMENT_TARGET'] = cfg_target
-        elif [int(x) for x in cfg_target.split('.')] > [int(x) for x in cur_target.split('.')]:
-            my_msg = ('$MACOSX_DEPLOYMENT_TARGET mismatch: now "%s" but "%s" during configure'
-                % (cur_target, cfg_target))
-            raise DistutilsPlatformError(my_msg)
-
     # On AIX, there are wrong paths to the linker scripts in the Makefile
     # -- these paths are relative to the Python source, but when installed
     # the scripts are in another directory.
diff --git a/Lib/distutils/tests/test_build_ext.py b/Lib/distutils/tests/test_build_ext.py
index d924f58..0ce7f0f 100644
--- a/Lib/distutils/tests/test_build_ext.py
+++ b/Lib/distutils/tests/test_build_ext.py
@@ -11,7 +11,8 @@
 from distutils.tests.support import LoggingSilencer
 from distutils.extension import Extension
 from distutils.errors import (
-    CompileError, DistutilsSetupError, UnknownFileError)
+    CompileError, DistutilsPlatformError, DistutilsSetupError,
+    UnknownFileError)
 
 import unittest
 from test import support
@@ -431,18 +432,43 @@
 
 
     @unittest.skipUnless(sys.platform == 'darwin', 'test only relevant for MacOSX')
-    def test_deployment_target(self):
-        self._try_compile_deployment_target()
+    def test_deployment_target_default(self):
+        # Issue 9516: Test that, in the absence of the environment variable,
+        # an extension module is compiled with the same deployment target as
+        #  the interpreter.
+        self._try_compile_deployment_target('==', None)
 
+    @unittest.skipUnless(sys.platform == 'darwin', 'test only relevant for MacOSX')
+    def test_deployment_target_too_low(self):
+        # Issue 9516: Test that an extension module is not allowed to be
+        # compiled with a deployment target less than that of the interpreter.
+        self.assertRaises(DistutilsPlatformError,
+            self._try_compile_deployment_target, '>', '10.1')
+
+    @unittest.skipUnless(sys.platform == 'darwin', 'test only relevant for MacOSX')
+    def test_deployment_target_higher_ok(self):
+        # Issue 9516: Test that an extension module can be compiled with a
+        # deployment target higher than that of the interpreter: the ext
+        # module may depend on some newer OS feature.
+        deptarget = sysconfig.get_config_var('MACOSX_DEPLOYMENT_TARGET')
+        if deptarget:
+            # increment the minor version number (i.e. 10.6 -> 10.7)
+            deptarget = [int(x) for x in deptarget.split('.')]
+            deptarget[-1] += 1
+            deptarget = '.'.join(str(i) for i in deptarget)
+            self._try_compile_deployment_target('<', deptarget)
+
+    def _try_compile_deployment_target(self, operator, target):
         orig_environ = os.environ
         os.environ = orig_environ.copy()
         self.addCleanup(setattr, os, 'environ', orig_environ)
 
-        os.environ['MACOSX_DEPLOYMENT_TARGET']='10.1'
-        self._try_compile_deployment_target()
+        if target is None:
+            if os.environ.get('MACOSX_DEPLOYMENT_TARGET'):
+                del os.environ['MACOSX_DEPLOYMENT_TARGET']
+        else:
+            os.environ['MACOSX_DEPLOYMENT_TARGET'] = target
 
-
-    def _try_compile_deployment_target(self):
         deptarget_c = os.path.join(self.tmp_dir, 'deptargetmodule.c')
 
         with open(deptarget_c, 'w') as fp:
@@ -451,16 +477,17 @@
 
                 int dummy;
 
-                #if TARGET != MAC_OS_X_VERSION_MIN_REQUIRED
+                #if TARGET %s MAC_OS_X_VERSION_MIN_REQUIRED
+                #else
                 #error "Unexpected target"
                 #endif
 
-            '''))
+            ''' % operator))
 
+        # get the deployment target that the interpreter was built with
         target = sysconfig.get_config_var('MACOSX_DEPLOYMENT_TARGET')
         target = tuple(map(int, target.split('.')))
         target = '%02d%01d0' % target
-
         deptarget_ext = Extension(
             'deptarget',
             [deptarget_c],
diff --git a/Misc/NEWS b/Misc/NEWS
index a8c6079..834dea6 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -25,6 +25,17 @@
 Library
 -------
 
+- Issue #9516: On Mac OS X, change Distutils to no longer globally attempt to
+  check or set the MACOSX_DEPLOYMENT_TARGET environment variable for the
+  interpreter process.  This could cause failures in non-Distutils subprocesses
+  and was unreliable since tests or user programs could modify the interpreter
+  environment after Distutils set it.  Instead, have Distutils set the the
+  deployment target only in the environment of each build subprocess.  It is
+  still possible to globally override the default by setting
+  MACOSX_DEPLOYMENT_TARGET before launching the interpreter; its value must be
+  greater or equal to the default value, the value with which the interpreter
+  was built.
+
 - Issue #12404: Remove C89 incompatible code from mmap module. Patch by Akira
   Kitada.