diff --git a/colorama/initialise.py b/colorama/initialise.py
index 430d066..eb114b9 100644
--- a/colorama/initialise.py
+++ b/colorama/initialise.py
@@ -5,9 +5,10 @@
 
 from .ansitowin32 import AnsiToWin32
 
+UNSET = object()
 
-orig_stdout = None
-orig_stderr = None
+orig_stdout = UNSET
+orig_stderr = UNSET
 
 wrapped_stdout = None
 wrapped_stderr = None
@@ -21,15 +22,17 @@ def reset_all():
 
 
 def init(autoreset=False, convert=None, strip=None, wrap=True):
-
     if not wrap and any([autoreset, convert, strip]):
         raise ValueError('wrap=False conflicts with any other arg=True')
 
     global wrapped_stdout, wrapped_stderr
     global orig_stdout, orig_stderr
 
-    orig_stdout = sys.stdout
-    orig_stderr = sys.stderr
+    # Prevent multiple calls from losing the original stdout/err
+    if orig_stdout is UNSET:
+        orig_stdout = sys.stdout
+    if orig_stderr is UNSET:
+        orig_stderr = sys.stderr
 
     if sys.stdout is None:
         wrapped_stdout = None
@@ -49,10 +52,13 @@ def init(autoreset=False, convert=None, strip=None, wrap=True):
 
 
 def deinit():
-    if orig_stdout is not None:
+    global orig_stdout, orig_stderr
+    if orig_stdout is not UNSET:
         sys.stdout = orig_stdout
-    if orig_stderr is not None:
+        orig_stdout = UNSET
+    if orig_stderr is not UNSET:
         sys.stderr = orig_stderr
+        orig_stderr = UNSET
 
 
 @contextlib.contextmanager
@@ -78,3 +84,4 @@ def wrap_stream(stream, convert, strip, autoreset, wrap):
         if wrapper.should_wrap():
             stream = wrapper.stream
     return stream
+
diff --git a/colorama/tests/initialise_test.py b/colorama/tests/initialise_test.py
index 2f7384d..0aac36e 100644
--- a/colorama/tests/initialise_test.py
+++ b/colorama/tests/initialise_test.py
@@ -6,7 +6,8 @@
 from mock import patch
 
 from ..ansitowin32 import StreamWrapper
-from ..initialise import init
+from .. import initialise
+from ..initialise import deinit, init
 from .utils import osname, redirected_output, replace_by
 
 orig_stdout = sys.stdout
@@ -22,6 +23,8 @@ def setUp(self):
     def tearDown(self):
         sys.stdout = orig_stdout
         sys.stderr = orig_stderr
+        initialise.orig_stdout = initialise.UNSET
+        initialise.orig_stderr = initialise.UNSET
 
     def assertWrapped(self):
         self.assertIsNot(sys.stdout, orig_stdout, 'stdout should be wrapped')
@@ -75,11 +78,29 @@ def testInitWrapOffDoesntWrapOnWindows(self):
     def testInitWrapOffIncompatibleWithAutoresetOn(self):
         self.assertRaises(ValueError, lambda: init(autoreset=True, wrap=False))
 
-    @patch('colorama.ansitowin32.winterm', None)
     @patch('colorama.ansitowin32.winapi_test', lambda *_: True)
-    def testInitOnlyWrapsOnce(self):
-        with osname("nt"):
+    def testInitTwiceCanBeUndoneWithDeinitOnce(self):
+        with osname('nt'):
+            self.assertNotWrapped()
+            init()
+            self.assertWrapped()
             init()
+            self.assertWrapped()
+            deinit()
+            self.assertNotWrapped()
+
+    @patch('colorama.ansitowin32.winapi_test', lambda *_: True)
+    def testInitDeinitInitWorks(self):
+        with osname('nt'):
+            self.assertNotWrapped()
+            init()
+            self.assertWrapped()
+            deinit()
+            self.assertNotWrapped()
+            init()
+            self.assertWrapped()
+            deinit()
+            self.assertNotWrapped()
             init()
             self.assertWrapped()
 
diff --git a/colorama/tests/utils.py b/colorama/tests/utils.py
index de2abf5..a8af441 100644
--- a/colorama/tests/utils.py
+++ b/colorama/tests/utils.py
@@ -18,16 +18,20 @@ def isatty(self):
 def osname(name):
     orig = os.name
     os.name = name
-    yield
-    os.name = orig
+    try:
+        yield
+    finally:
+        os.name = orig
 
 @contextmanager
 def redirected_output():
     orig = sys.stdout
     sys.stdout = Mock()
     sys.stdout.isatty = lambda: False
-    yield
-    sys.stdout = orig
+    try:
+        yield
+    finally:
+        sys.stdout = orig
 
 @contextmanager
 def replace_by(stream):
@@ -35,9 +39,11 @@ def replace_by(stream):
     orig_stderr = sys.stderr
     sys.stdout = stream
     sys.stderr = stream
-    yield
-    sys.stdout = orig_stdout
-    sys.stderr = orig_stderr
+    try:
+        yield
+    finally:
+        sys.stdout = orig_stdout
+        sys.stderr = orig_stderr
 
 @contextmanager
 def replace_original_by(stream):
@@ -45,14 +51,19 @@ def replace_original_by(stream):
     orig_stderr = sys.__stderr__
     sys.__stdout__ = stream
     sys.__stderr__ = stream
-    yield
-    sys.__stdout__ = orig_stdout
-    sys.__stderr__ = orig_stderr
+    try:
+        yield
+    finally:
+        sys.__stdout__ = orig_stdout
+        sys.__stderr__ = orig_stderr
 
 @contextmanager
 def pycharm():
     os.environ["PYCHARM_HOSTED"] = "1"
     non_tty = StreamNonTTY()
-    with replace_by(non_tty), replace_original_by(non_tty):
-        yield
-    del os.environ["PYCHARM_HOSTED"]
+    try:
+        with replace_by(non_tty), replace_original_by(non_tty):
+            yield
+    finally:
+        del os.environ["PYCHARM_HOSTED"]
+