diff --git a/pubsub/google/cloud/pubsub_v1/_gapic.py b/pubsub/google/cloud/pubsub_v1/_gapic.py
index 25cb3e5fa33c..da755dfbca09 100644
--- a/pubsub/google/cloud/pubsub_v1/_gapic.py
+++ b/pubsub/google/cloud/pubsub_v1/_gapic.py
@@ -1,4 +1,4 @@
-# Copyright 2017, Google LLC All rights reserved.
+# Copyright 2019, Google LLC All rights reserved.
 #
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
@@ -25,29 +25,21 @@ def add_methods(source_class, blacklist=()):
     not added.
     """
 
-    def wrap(wrapped_fx):
+    def wrap(wrapped_fx, lookup_fx):
         """Wrap a GAPIC method; preserve its name and docstring."""
-        # If this is a static or class method, then we need to *not*
+        # If this is a static or class method, then we do *not*
         # send self as the first argument.
         #
-        # Similarly, for instance methods, we need to send self.api rather
+        # For instance methods, we need to send self.api rather
         # than self, since that is where the actual methods were declared.
-        instance_method = True
 
-        # If this is a bound method it's a classmethod.
-        self = getattr(wrapped_fx, "__self__", None)
-        if issubclass(type(self), type):
-            instance_method = False
-
-        # Okay, we have figured out what kind of method this is; send
-        # down the correct wrapper function.
-        if instance_method:
+        if isinstance(lookup_fx, (classmethod, staticmethod)):
+            fx = lambda *a, **kw: wrapped_fx(*a, **kw)  # noqa
+            return staticmethod(functools.wraps(wrapped_fx)(fx))
+        else:
             fx = lambda self, *a, **kw: wrapped_fx(self.api, *a, **kw)  # noqa
             return functools.wraps(wrapped_fx)(fx)
 
-        fx = lambda *a, **kw: wrapped_fx(*a, **kw)  # noqa
-        return staticmethod(functools.wraps(wrapped_fx)(fx))
-
     def actual_decorator(cls):
         # Reflectively iterate over most of the methods on the source class
         # (the GAPIC) and make wrapped versions available on this client.
@@ -66,7 +58,9 @@ def actual_decorator(cls):
                 continue
 
             # Add a wrapper method to this object.
-            fx = wrap(getattr(source_class, name))
+            lookup_fx = source_class.__dict__[name]
+            fx = wrap(attr, lookup_fx)
+
             setattr(cls, name, fx)
 
         # Return the augmented class.
diff --git a/pubsub/tests/unit/pubsub_v1/test__gapic.py b/pubsub/tests/unit/pubsub_v1/test__gapic.py
new file mode 100644
index 000000000000..5478aee18213
--- /dev/null
+++ b/pubsub/tests/unit/pubsub_v1/test__gapic.py
@@ -0,0 +1,63 @@
+# Copyright 2019 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     https://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+
+from google.cloud.pubsub_v1 import _gapic
+
+
+class SourceClass(object):
+    def __init__(self):
+        self.x = "x"
+
+    def method(self):
+        return "source class instance method"
+
+    @staticmethod
+    def static_method():
+        return "source class static method"
+
+    @classmethod
+    def class_method(cls):
+        return "source class class method"
+
+    @classmethod
+    def blacklisted_method(cls):
+        return "source class blacklisted method"
+
+
+def test_add_method():
+    @_gapic.add_methods(SourceClass, ("blacklisted_method",))
+    class Foo(object):
+        def __init__(self):
+            self.api = SourceClass()
+
+        def method(self):
+            return "foo class instance method"
+
+    foo = Foo()
+
+    # Any method that's callable and not blacklisted is "inherited".
+    assert set(["method", "static_method", "class_method"]) <= set(dir(foo))
+    assert "blacklisted_method" not in dir(foo)
+
+    # Source Class's static and class methods become static methods.
+    assert type(Foo.__dict__["static_method"]) == staticmethod
+    assert foo.static_method() == "source class static method"
+    assert type(Foo.__dict__["class_method"]) == staticmethod
+    assert foo.class_method() == "source class class method"
+
+    # The decorator changes the behavior of instance methods of the wrapped class.
+    # method() is called on an instance of the Source Class (stored as an
+    # attribute on the wrapped class).
+    assert foo.method() == "source class instance method"