diff --git a/changelog/5239.trivial.rst b/changelog/5239.trivial.rst
new file mode 100644
index 000000000..5bd7389f3
--- /dev/null
+++ b/changelog/5239.trivial.rst
@@ -0,0 +1,3 @@
+Pin ``pluggy`` to ``< 1.0`` so we don't update to ``1.0`` automatically when
+it gets released: there are planned breaking changes, and we want to ensure
+pytest properly supports ``pluggy 1.0``.
diff --git a/setup.py b/setup.py
index 08c559c93..1a7184cc3 100644
--- a/setup.py
+++ b/setup.py
@@ -13,7 +13,7 @@ INSTALL_REQUIRES = [
     'funcsigs>=1.0;python_version<"3.0"',
     'pathlib2>=2.2.0;python_version<"3.6"',
     'colorama;sys_platform=="win32"',
-    "pluggy>=0.11",
+    "pluggy>=0.9,!=0.10,<1.0",
 ]