diff --git a/.github/workflows/CI.yml b/.github/workflows/CI.yml
index 5f1517744..8f63039fb 100644
--- a/.github/workflows/CI.yml
+++ b/.github/workflows/CI.yml
@@ -2,7 +2,7 @@
 # On a pull requests and on pushes to master it will run different tests for elephant.
 
 name: tests
-# define events that trigger workflow 'tests'
+# Define events that trigger workflow 'tests'
 on:
   workflow_dispatch: # enables manual triggering of workflow
     inputs:
@@ -42,7 +42,12 @@ on:
     branches:
       - master
 
-# jobs define the steps that will be executed on the runner
+# Cancel previous workflows on the same pull request
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
+# Jobs define the steps that will be executed on the runner
 jobs:
 
   #        _