diff --git a/.flake8 b/.flake8
index ed931638..29227d4c 100644
--- a/.flake8
+++ b/.flake8
@@ -26,6 +26,7 @@ exclude =
   *_pb2.py
 
   # Standard linting exemptions.
+  **/.nox/**
   __pycache__,
   .git,
   *.pyc,
diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
new file mode 100644
index 00000000..a9024b15
--- /dev/null
+++ b/.pre-commit-config.yaml
@@ -0,0 +1,17 @@
+# See https://pre-commit.com for more information
+# See https://pre-commit.com/hooks.html for more hooks
+repos:
+-   repo: https://github.com/pre-commit/pre-commit-hooks
+    rev: v3.4.0
+    hooks:
+    -   id: trailing-whitespace
+    -   id: end-of-file-fixer
+    -   id: check-yaml
+-   repo: https://github.com/psf/black
+    rev: 19.10b0
+    hooks:
+    - id: black
+-   repo: https://gitlab.com/pycqa/flake8
+    rev: 3.8.4
+    hooks:
+    - id: flake8
diff --git a/CONTRIBUTING.rst b/CONTRIBUTING.rst
index 43384e74..ecad28ae 100644
--- a/CONTRIBUTING.rst
+++ b/CONTRIBUTING.rst
@@ -21,8 +21,8 @@ In order to add a feature:
 - The feature must be documented in both the API and narrative
   documentation.
 
-- The feature must work fully on the following CPython versions:  2.7,
-  3.5, 3.6, 3.7 and 3.8 on both UNIX and Windows.
+- The feature must work fully on the following CPython versions:
+  3.6, 3.7, 3.8 and 3.9 on both UNIX and Windows.
 
 - The feature must not add unnecessary dependencies (where
   "unnecessary" is of course subjective, but new dependencies should
@@ -111,6 +111,16 @@ Coding Style
   should point to the official ``googleapis`` checkout and the
   the branch should be the main branch on that remote (``master``).
 
+- This repository contains configuration for the
+  `pre-commit <https://pre-commit.com/>`__ tool, which automates checking
+  our linters during a commit.  If you have it installed on your ``$PATH``,
+  you can enable enforcing those checks via:
+
+.. code-block:: bash
+
+   $ pre-commit install
+   pre-commit installed at .git/hooks/pre-commit
+
 Exceptions to PEP8:
 
 - Many unit tests use a helper method, ``_call_fut`` ("FUT" is short for
@@ -192,25 +202,24 @@ Supported Python Versions
 
 We support:
 
--  `Python 3.5`_
 -  `Python 3.6`_
 -  `Python 3.7`_
 -  `Python 3.8`_
+-  `Python 3.9`_
 
-.. _Python 3.5: https://docs.python.org/3.5/
 .. _Python 3.6: https://docs.python.org/3.6/
 .. _Python 3.7: https://docs.python.org/3.7/
 .. _Python 3.8: https://docs.python.org/3.8/
+.. _Python 3.9: https://docs.python.org/3.9/
 
 
 Supported versions can be found in our ``noxfile.py`` `config`_.
 
 .. _config: https://github.com/googleapis/python-dataproc/blob/master/noxfile.py
 
-Python 2.7 support is deprecated. All code changes should maintain Python 2.7 compatibility until January 1, 2020.
 
 We also explicitly decided to support Python 3 beginning with version
-3.5. Reasons for this include:
+3.6. Reasons for this include:
 
 -  Encouraging use of newest versions of Python 3
 -  Taking the lead of `prominent`_ open-source `projects`_
diff --git a/docs/conf.py b/docs/conf.py
index 9c46a0ba..5725bc93 100644
--- a/docs/conf.py
+++ b/docs/conf.py
@@ -345,10 +345,10 @@
 
 # Example configuration for intersphinx: refer to the Python standard library.
 intersphinx_mapping = {
-    "python": ("http://python.readthedocs.org/en/latest/", None),
-    "google-auth": ("https://google-auth.readthedocs.io/en/stable", None),
+    "python": ("https://python.readthedocs.org/en/latest/", None),
+    "google-auth": ("https://googleapis.dev/python/google-auth/latest/", None),
     "google.api_core": ("https://googleapis.dev/python/google-api-core/latest/", None,),
-    "grpc": ("https://grpc.io/grpc/python/", None),
+    "grpc": ("https://grpc.github.io/grpc/python/", None),
     "proto-plus": ("https://proto-plus-python.readthedocs.io/en/latest/", None),
 }
 
diff --git a/noxfile.py b/noxfile.py
index f3ed2bed..f230390f 100644
--- a/noxfile.py
+++ b/noxfile.py
@@ -81,9 +81,8 @@ def default(session):
     session.run(
         "py.test",
         "--quiet",
-        "--cov=google.cloud.dataproc",
-        "--cov=google.cloud",
-        "--cov=tests.unit",
+        "--cov=google/cloud",
+        "--cov=tests/unit",
         "--cov-append",
         "--cov-config=.coveragerc",
         "--cov-report=",
diff --git a/samples/snippets/noxfile.py b/samples/snippets/noxfile.py
index b90eef00..bca0522e 100644
--- a/samples/snippets/noxfile.py
+++ b/samples/snippets/noxfile.py
@@ -17,6 +17,7 @@
 import os
 from pathlib import Path
 import sys
+from typing import Callable, Dict, List, Optional
 
 import nox
 
@@ -68,7 +69,7 @@
 TEST_CONFIG.update(TEST_CONFIG_OVERRIDE)
 
 
-def get_pytest_env_vars():
+def get_pytest_env_vars() -> Dict[str, str]:
     """Returns a dict for pytest invocation."""
     ret = {}
 
@@ -97,7 +98,7 @@ def get_pytest_env_vars():
 #
 
 
-def _determine_local_import_names(start_dir):
+def _determine_local_import_names(start_dir: str) -> List[str]:
     """Determines all import names that should be considered "local".
 
     This is used when running the linter to insure that import order is
@@ -135,7 +136,7 @@ def _determine_local_import_names(start_dir):
 
 
 @nox.session
-def lint(session):
+def lint(session: nox.sessions.Session) -> None:
     if not TEST_CONFIG['enforce_type_hints']:
         session.install("flake8", "flake8-import-order")
     else:
@@ -154,7 +155,7 @@ def lint(session):
 
 
 @nox.session
-def blacken(session):
+def blacken(session: nox.sessions.Session) -> None:
     session.install("black")
     python_files = [path for path in os.listdir(".") if path.endswith(".py")]
 
@@ -168,7 +169,7 @@ def blacken(session):
 PYTEST_COMMON_ARGS = ["--junitxml=sponge_log.xml"]
 
 
-def _session_tests(session, post_install=None):
+def _session_tests(session: nox.sessions.Session, post_install: Callable = None) -> None:
     """Runs py.test for a particular project."""
     if os.path.exists("requirements.txt"):
         session.install("-r", "requirements.txt")
@@ -194,7 +195,7 @@ def _session_tests(session, post_install=None):
 
 
 @nox.session(python=ALL_VERSIONS)
-def py(session):
+def py(session: nox.sessions.Session) -> None:
     """Runs py.test for a sample using the specified version of Python."""
     if session.python in TESTED_VERSIONS:
         _session_tests(session)
@@ -209,7 +210,7 @@ def py(session):
 #
 
 
-def _get_repo_root():
+def _get_repo_root() -> Optional[str]:
     """ Returns the root folder of the project. """
     # Get root of this repository. Assume we don't have directories nested deeper than 10 items.
     p = Path(os.getcwd())
@@ -232,7 +233,7 @@ def _get_repo_root():
 
 @nox.session
 @nox.parametrize("path", GENERATED_READMES)
-def readmegen(session, path):
+def readmegen(session: nox.sessions.Session, path: str) -> None:
     """(Re-)generates the readme for a sample."""
     session.install("jinja2", "pyyaml")
     dir_ = os.path.dirname(path)
diff --git a/synth.metadata b/synth.metadata
index 209ee4ba..44bc8d9c 100644
--- a/synth.metadata
+++ b/synth.metadata
@@ -19,14 +19,14 @@
       "git": {
         "name": "synthtool",
         "remote": "https://github.com/googleapis/synthtool.git",
-        "sha": "7fcc405a579d5d53a726ff3da1b7c8c08f0f2d58"
+        "sha": "373861061648b5fe5e0ac4f8a38b32d639ee93e4"
       }
     },
     {
       "git": {
         "name": "synthtool",
         "remote": "https://github.com/googleapis/synthtool.git",
-        "sha": "7fcc405a579d5d53a726ff3da1b7c8c08f0f2d58"
+        "sha": "373861061648b5fe5e0ac4f8a38b32d639ee93e4"
       }
     }
   ],
@@ -94,6 +94,7 @@
     ".kokoro/test-samples.sh",
     ".kokoro/trampoline.sh",
     ".kokoro/trampoline_v2.sh",
+    ".pre-commit-config.yaml",
     ".trampolinerc",
     "CODE_OF_CONDUCT.md",
     "CONTRIBUTING.rst",