diff --git a/.github/workflows/main.yml b/.github/workflows/main.yml
index 81fa9630..63bbfee3 100644
--- a/.github/workflows/main.yml
+++ b/.github/workflows/main.yml
@@ -27,7 +27,7 @@ jobs:
       
       - name: Install Poetry
         run: |
-          curl -sSL https://install.python-poetry.org | python3 -
+          curl -sSL https://install.python-poetry.org | python3 - --version 1.8.5
           echo "$HOME/.local/bin" >> $GITHUB_PATH
 
       - name: Install dependencies
diff --git a/README.md b/README.md
index e8fa73a3..4eaf0236 100644
--- a/README.md
+++ b/README.md
@@ -27,7 +27,7 @@ tools.  Here is a quick tour of the our EZID `pyproject.toml`:
 We declare Poetry as our build tool
 ```
 [build-system]
-requires = ["poetry-core>=1.0.0"]
+requires = ["poetry-core>=1.0.0,<2.0.0"]
 build-backend = "poetry.core.masonry.api"
 ```
 
diff --git a/ansible/roles/ezid/tasks/configure_ezid.yaml b/ansible/roles/ezid/tasks/configure_ezid.yaml
index 595adb34..7f907480 100644
--- a/ansible/roles/ezid/tasks/configure_ezid.yaml
+++ b/ansible/roles/ezid/tasks/configure_ezid.yaml
@@ -24,7 +24,7 @@
 
 - name: install poetry
   ansible.builtin.pip:
-    name: poetry
+    name: poetry==1.8.5
 
 - name: run pip install
   ansible.builtin.command:
diff --git a/pyproject.toml b/pyproject.toml
index 5f3ec3bf..f24842e7 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,5 +1,5 @@
 [build-system]
-requires = ["poetry-core>=1.0.0"]
+requires = ["poetry-core>=1.0.0,<2.0.0"]
 build-backend = "poetry.core.masonry.api"
 
 [tool.black]