diff --git a/.github/workflows/bootstrap.yml b/.github/workflows/bootstrap.yml
index 37804293867..fce8c81d1f3 100644
--- a/.github/workflows/bootstrap.yml
+++ b/.github/workflows/bootstrap.yml
@@ -19,6 +19,10 @@ on:
     # nightly at 2:16 AM
     - cron: '16 2 * * *'
 
+concurrency:
+  group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.run_number }}
+  cancel-in-progress: true
+
 jobs:
 
   fedora-clingo-sources:
diff --git a/.github/workflows/build-containers.yml b/.github/workflows/build-containers.yml
index 5057a89a455..90e01b67af5 100644
--- a/.github/workflows/build-containers.yml
+++ b/.github/workflows/build-containers.yml
@@ -19,6 +19,10 @@ on:
   release:
     types: [published]
 
+concurrency:
+  group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.run_number }}
+  cancel-in-progress: true
+
 jobs:
   deploy-images:
     runs-on: ubuntu-latest
diff --git a/.github/workflows/macos_python.yml b/.github/workflows/macos_python.yml
index 130a1bf70b3..55e3997d0ec 100644
--- a/.github/workflows/macos_python.yml
+++ b/.github/workflows/macos_python.yml
@@ -16,6 +16,10 @@ on:
       - '.github/workflows/macos_python.yml'
       # TODO: run if we touch any of the recipes involved in this
 
+concurrency:
+  group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.run_number }}
+  cancel-in-progress: true
+
 # GitHub Action Limits
 # https://help.github.com/en/actions/reference/workflow-syntax-for-github-actions
 
diff --git a/.github/workflows/unit_tests.yaml b/.github/workflows/unit_tests.yaml
index 66cf79380ea..6de8ce7fedd 100644
--- a/.github/workflows/unit_tests.yaml
+++ b/.github/workflows/unit_tests.yaml
@@ -9,6 +9,11 @@ on:
     branches:
       - develop
       - releases/**
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.run_number }}
+  cancel-in-progress: true
+
 jobs:
   # Validate that the code can be run on all the Python versions
   # supported by Spack
diff --git a/.github/workflows/windows_python.yml b/.github/workflows/windows_python.yml
index 4707cab4169..1b3332fef53 100644
--- a/.github/workflows/windows_python.yml
+++ b/.github/workflows/windows_python.yml
@@ -9,6 +9,11 @@ on:
     branches:
       - develop
       - releases/**
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.event.pull_request.number || github.run_number }}
+  cancel-in-progress: true
+
 defaults:
   run:
     shell: