diff --git a/docs/_config.yml b/docs/_config.yml
index cfa474b..c8af239 100644
--- a/docs/_config.yml
+++ b/docs/_config.yml
@@ -25,6 +25,9 @@ description: >- # this means to ignore newlines until "baseurl:"
 baseurl: "" # the subpath of your site, e.g. /blog
 url: "https://notify.nhs.uk" # the base hostname & protocol for your site, e.g. http://example.com
 
+# Google Analytics 4
+# google_analytics: G-XXXXXXXXXX
+
 collections_dir: collections
 
 collections:
diff --git a/docs/_layouts/default.html b/docs/_layouts/default.html
index ab3c23c..3b11301 100644
--- a/docs/_layouts/default.html
+++ b/docs/_layouts/default.html
@@ -21,6 +21,17 @@
   <meta name="msapplication-square150x150logo" content="{{site.baseurl}}/assets/favicons/mediumtile-150x150.png">
   <meta name="msapplication-wide310x150logo" content="{{site.baseurl}}/assets/favicons/widetile-310x150.png">
   <meta name="msapplication-square310x310logo" content="{{site.baseurl}}/assets/favicons/largetile-310x310.png">
+
+  {% if site.google_analytics %}
+  <!-- Google tag (gtag.js) -->
+  <script async src="https://www.googletagmanager.com/gtag/js?id={{ site.google_analytics }}"></script>
+  <script>
+    window.dataLayer = window.dataLayer || [];
+    function gtag(){dataLayer.push(arguments);}
+    gtag('js', new Date());
+    gtag('config', '{{ site.google_analytics }}');
+  </script>
+  {% endif %}
 </head>
 
 <body class="wrap">
