diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index c1d5647..4e28eab 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -15,6 +15,19 @@ jobs:
       - uses: actions/checkout@v2
       - name: Black Check
         uses: jpetrucciani/black-check@20.8b1
+  mypy:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - uses: actions/setup-python@v2
+        with:
+          python-version: "3.9"
+      - uses: Gr1N/setup-poetry@v4
+      - run: poetry install
+      - run: poetry run mypy --py2 sysaudit/ tests/
+        name: Mypy Check Python2
+      - run: poetry run mypy sysaudit/ tests/
+        name: Mypy Check Python3
   test:
     runs-on: ubuntu-latest
     strategy:
diff --git a/poetry.lock b/poetry.lock
index 982ed89..3ad7437 100644
--- a/poetry.lock
+++ b/poetry.lock
@@ -177,6 +177,22 @@ category = "dev"
 optional = false
 python-versions = ">=3.5"
 
+[[package]]
+name = "mypy"
+version = "0.800"
+description = "Optional static typing for Python"
+category = "dev"
+optional = false
+python-versions = ">=3.5"
+
+[package.dependencies]
+mypy-extensions = ">=0.4.3,<0.5.0"
+typed-ast = ">=1.4.0,<1.5.0"
+typing-extensions = ">=3.7.4"
+
+[package.extras]
+dmypy = ["psutil (>=4.0)"]
+
 [[package]]
 name = "mypy-extensions"
 version = "0.4.3"
@@ -314,6 +330,14 @@ category = "dev"
 optional = false
 python-versions = "*"
 
+[[package]]
+name = "typing"
+version = "3.7.4.3"
+description = "Type Hints for Python"
+category = "dev"
+optional = false
+python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*"
+
 [[package]]
 name = "typing-extensions"
 version = "3.7.4.3"
@@ -351,7 +375,7 @@ testing = ["pathlib2", "unittest2", "jaraco.itertools", "func-timeout"]
 [metadata]
 lock-version = "1.1"
 python-versions = "~2.7 || ~=3.5"
-content-hash = "0c50ae6c648ef29d97374fa76541950369bf55f54f8bc3fe6e4df19b9d500638"
+content-hash = "fe83468734284b10f0b424dab2cf20729e7feab41eac731cc1b7e86b4accc4f1"
 
 [metadata.files]
 appdirs = [
@@ -449,6 +473,30 @@ more-itertools = [
     {file = "more-itertools-8.7.0.tar.gz", hash = "sha256:c5d6da9ca3ff65220c3bfd2a8db06d698f05d4d2b9be57e1deb2be5a45019713"},
     {file = "more_itertools-8.7.0-py3-none-any.whl", hash = "sha256:5652a9ac72209ed7df8d9c15daf4e1aa0e3d2ccd3c87f8265a0673cd9cbc9ced"},
 ]
+mypy = [
+    {file = "mypy-0.800-cp35-cp35m-macosx_10_9_x86_64.whl", hash = "sha256:e1c84c65ff6d69fb42958ece5b1255394714e0aac4df5ffe151bc4fe19c7600a"},
+    {file = "mypy-0.800-cp35-cp35m-manylinux1_x86_64.whl", hash = "sha256:947126195bfe4709c360e89b40114c6746ae248f04d379dca6f6ab677aa07641"},
+    {file = "mypy-0.800-cp35-cp35m-manylinux2010_x86_64.whl", hash = "sha256:b95068a3ce3b50332c40e31a955653be245666a4bc7819d3c8898aa9fb9ea496"},
+    {file = "mypy-0.800-cp35-cp35m-win_amd64.whl", hash = "sha256:ca7ad5aed210841f1e77f5f2f7d725b62c78fa77519312042c719ed2ab937876"},
+    {file = "mypy-0.800-cp36-cp36m-macosx_10_9_x86_64.whl", hash = "sha256:e32b7b282c4ed4e378bba8b8dfa08e1cfa6f6574067ef22f86bee5b1039de0c9"},
+    {file = "mypy-0.800-cp36-cp36m-manylinux1_x86_64.whl", hash = "sha256:e497a544391f733eca922fdcb326d19e894789cd4ff61d48b4b195776476c5cf"},
+    {file = "mypy-0.800-cp36-cp36m-manylinux2010_x86_64.whl", hash = "sha256:5615785d3e2f4f03ab7697983d82c4b98af5c321614f51b8f1034eb9ebe48363"},
+    {file = "mypy-0.800-cp36-cp36m-win_amd64.whl", hash = "sha256:2b216eacca0ec0ee124af9429bfd858d5619a0725ee5f88057e6e076f9eb1a7b"},
+    {file = "mypy-0.800-cp37-cp37m-macosx_10_9_x86_64.whl", hash = "sha256:e3b8432f8df19e3c11235c4563a7250666dc9aa7cdda58d21b4177b20256ca9f"},
+    {file = "mypy-0.800-cp37-cp37m-manylinux1_x86_64.whl", hash = "sha256:d16c54b0dffb861dc6318a8730952265876d90c5101085a4bc56913e8521ba19"},
+    {file = "mypy-0.800-cp37-cp37m-manylinux2010_x86_64.whl", hash = "sha256:0d2fc8beb99cd88f2d7e20d69131353053fbecea17904ee6f0348759302c52fa"},
+    {file = "mypy-0.800-cp37-cp37m-win_amd64.whl", hash = "sha256:aa9d4901f3ee1a986a3a79fe079ffbf7f999478c281376f48faa31daaa814e86"},
+    {file = "mypy-0.800-cp38-cp38-macosx_10_9_x86_64.whl", hash = "sha256:319ee5c248a7c3f94477f92a729b7ab06bf8a6d04447ef3aa8c9ba2aa47c6dcf"},
+    {file = "mypy-0.800-cp38-cp38-manylinux1_x86_64.whl", hash = "sha256:74f5aa50d0866bc6fb8e213441c41e466c86678c800700b87b012ed11c0a13e0"},
+    {file = "mypy-0.800-cp38-cp38-manylinux2010_x86_64.whl", hash = "sha256:a301da58d566aca05f8f449403c710c50a9860782148332322decf73a603280b"},
+    {file = "mypy-0.800-cp38-cp38-win_amd64.whl", hash = "sha256:b9150db14a48a8fa114189bfe49baccdff89da8c6639c2717750c7ae62316738"},
+    {file = "mypy-0.800-cp39-cp39-macosx_10_9_x86_64.whl", hash = "sha256:f5fdf935a46aa20aa937f2478480ebf4be9186e98e49cc3843af9a5795a49a25"},
+    {file = "mypy-0.800-cp39-cp39-manylinux1_x86_64.whl", hash = "sha256:6f8425fecd2ba6007e526209bb985ce7f49ed0d2ac1cc1a44f243380a06a84fb"},
+    {file = "mypy-0.800-cp39-cp39-manylinux2010_x86_64.whl", hash = "sha256:5ff616787122774f510caeb7b980542a7cc2222be3f00837a304ea85cd56e488"},
+    {file = "mypy-0.800-cp39-cp39-win_amd64.whl", hash = "sha256:90b6f46dc2181d74f80617deca611925d7e63007cf416397358aa42efb593e07"},
+    {file = "mypy-0.800-py3-none-any.whl", hash = "sha256:3e0c159a7853e3521e3f582adb1f3eac66d0b0639d434278e2867af3a8c62653"},
+    {file = "mypy-0.800.tar.gz", hash = "sha256:e0202e37756ed09daf4b0ba64ad2c245d357659e014c3f51d8cd0681ba66940a"},
+]
 mypy-extensions = [
     {file = "mypy_extensions-0.4.3-py2.py3-none-any.whl", hash = "sha256:090fedd75945a69ae91ce1303b5824f428daf5a028d2f6ab8a299250a846f15d"},
     {file = "mypy_extensions-0.4.3.tar.gz", hash = "sha256:2d82818f5bb3e369420cb3c4060a7970edba416647068eb4c5343488a6c604a8"},
@@ -577,6 +625,10 @@ typed-ast = [
     {file = "typed_ast-1.4.2-cp39-cp39-win_amd64.whl", hash = "sha256:7147e2a76c75f0f64c4319886e7639e490fee87c9d25cb1d4faef1d8cf83a440"},
     {file = "typed_ast-1.4.2.tar.gz", hash = "sha256:9fc0b3cb5d1720e7141d103cf4819aea239f7d136acf9ee4a69b047b7986175a"},
 ]
+typing = [
+    {file = "typing-3.7.4.3-py2-none-any.whl", hash = "sha256:283d868f5071ab9ad873e5e52268d611e851c870a2ba354193026f2dfb29d8b5"},
+    {file = "typing-3.7.4.3.tar.gz", hash = "sha256:1187fb9c82fd670d10aa07bbb6cfcfe4bdda42d6fab8d5134f04e8c4d0b71cc9"},
+]
 typing-extensions = [
     {file = "typing_extensions-3.7.4.3-py2-none-any.whl", hash = "sha256:dafc7639cde7f1b6e1acc0f457842a83e722ccca8eef5270af2d74792619a89f"},
     {file = "typing_extensions-3.7.4.3-py3-none-any.whl", hash = "sha256:7cb407020f00f7bfc3cb3e7881628838e69d8f3fcab2f64742a5e76b2f841918"},
diff --git a/pyproject.toml b/pyproject.toml
index ba8508f..eca6311 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -17,6 +17,8 @@ Cython = "^0.29.21"
 black = {version = "^20.8b1", python = "~=3.6"}
 pytest = {version = "~=4.6"}
 mock = "~=3.0"
+mypy = {version = "~=0.800", python = "~=3.5"}
+typing = {version = "~=3.7.4", python = "~=2.7"}
 
 [build-system]
 requires = ["poetry-core>=1.0.0", "Cython", "setuptools"]
diff --git a/sysaudit/__init__.pyi b/sysaudit/__init__.pyi
new file mode 100644
index 0000000..cd66550
--- /dev/null
+++ b/sysaudit/__init__.pyi
@@ -0,0 +1,6 @@
+import typing
+
+def audit(event: str, *args: typing.Any) -> None: ...
+def addaudithook(
+    hook: typing.Callable[[str, typing.Tuple[typing.Any, ...]], None]
+) -> None: ...
diff --git a/sysaudit/_csysaudit.pyi b/sysaudit/_csysaudit.pyi
new file mode 100644
index 0000000..cd66550
--- /dev/null
+++ b/sysaudit/_csysaudit.pyi
@@ -0,0 +1,6 @@
+import typing
+
+def audit(event: str, *args: typing.Any) -> None: ...
+def addaudithook(
+    hook: typing.Callable[[str, typing.Tuple[typing.Any, ...]], None]
+) -> None: ...
diff --git a/sysaudit/py.typed b/sysaudit/py.typed
new file mode 100644
index 0000000..e69de29
diff --git a/tests/audit-tests.py b/tests/audit-tests.py
index 99e00f0..4358408 100644
--- a/tests/audit-tests.py
+++ b/tests/audit-tests.py
@@ -6,6 +6,7 @@ module with arguments identifying each test.
 """
 
 import contextlib
+import typing
 import sys
 
 import sysaudit
@@ -24,7 +25,7 @@ class TestHook:
         self.seen = []
         self.closed = False
 
-    def __enter__(self, *a):
+    def __enter__(self, *a):  # type: (typing.Any) -> TestHook
         sysaudit.addaudithook(self)
         return self
 
@@ -38,7 +39,9 @@ class TestHook:
     def seen_events(self):
         return [i[0] for i in self.seen]
 
-    def __call__(self, event, args):
+    def __call__(
+        self, event, args
+    ):  # type: (str, typing.Tuple[typing.Any, ...]) -> None
         if self.closed:
             return
         self.seen.append((event, args))
@@ -246,12 +249,12 @@ def test_mmap():
         assertEqual(hook.seen[0][1][:2], (-1, 8))
 
 
-def test_excepthook():
+def test_excepthook():  # type: () -> None
     def excepthook(exc_type, exc_value, exc_tb):
         if exc_type is not RuntimeError:
             sys.__excepthook__(exc_type, exc_value, exc_tb)
 
-    def hook(event, args):
+    def hook(event, args):  # type: (str, typing.Tuple[typing.Any, ...]) -> None
         if event == "sys.excepthook":
             if not isinstance(args[2], args[1]):
                 raise TypeError(
@@ -266,27 +269,27 @@ def test_excepthook():
     raise RuntimeError("fatal-error")
 
 
-def test_unraisablehook():
-    from _testcapi import write_unraisable_exc
+def test_unraisablehook():  # type: () -> None
+    from _testcapi import write_unraisable_exc  # type: ignore
 
     def unraisablehook(hookargs):
         pass
 
-    def hook(event, args):
+    def hook(event, args):  # type: (str, typing.Tuple[typing.Any, ...]) -> None
         if event == "sys.unraisablehook":
             if args[0] != unraisablehook:
                 raise ValueError("Expected {} == {}".format(args[0], unraisablehook))
             print(event, repr(args[1].exc_value), args[1].err_msg)
 
     sysaudit.addaudithook(hook)
-    sys.unraisablehook = unraisablehook
+    sys.unraisablehook = unraisablehook  # type: ignore [attr-defined]
     write_unraisable_exc(RuntimeError("nonfatal-error"), "for audit hook test", None)
 
 
-def test_winreg():
-    from winreg import OpenKey, EnumKey, CloseKey, HKEY_LOCAL_MACHINE
+def test_winreg():  # type: () -> None
+    from winreg import OpenKey, EnumKey, CloseKey, HKEY_LOCAL_MACHINE  # type: ignore
 
-    def hook(event, args):
+    def hook(event, args):  # type: (str, typing.Tuple[typing.Any, ...]) -> None
         if not event.startswith("winreg."):
             return
         print(event, args)
@@ -306,10 +309,10 @@ def test_winreg():
     CloseKey(kv)
 
 
-def test_socket():
+def test_socket():  # type: () -> None
     import socket
 
-    def hook(event, args):
+    def hook(event, args):  # type: (str, typing.Tuple[typing.Any, ...]) -> None
         if event.startswith("socket."):
             print(event, args)
 
diff --git a/tests/test_import.py b/tests/test_import.py
index 064b148..7842bf5 100644
--- a/tests/test_import.py
+++ b/tests/test_import.py
@@ -3,10 +3,10 @@ import sys
 import sysaudit
 
 
-def test_module():
+def test_module():  # type: () -> None
     if sys.version_info >= (3, 8, 0):
-        assert sysaudit.audit == sys.audit
-        assert sysaudit.addaudithook == sys.addaudithook
+        assert sysaudit.audit == sys.audit  # type: ignore [attr-defined]
+        assert sysaudit.addaudithook == sys.addaudithook  # type: ignore [attr-defined]
     else:
         assert sysaudit.audit == sysaudit._csysaudit.audit
         assert sysaudit.addaudithook == sysaudit._csysaudit.addaudithook