Addind a Consent Management Platform (CMP) is crucial within the EU to adhere to GDPR regulations. While it might be cumbersome in some cases to install one through the regular means of GTM, the process is pretty much stratforward with the ClientConscious tag, which provides a two-step way to perform this action.

Add a ClientConscious tag to your GTM container as shown in the Setup with GTM article ( or open one that you would like to modify ) and you will find the section on CMPs in the very top.

You only have to choose the CMP that you have registered with from the dropdown list of supported Consent Management Platforms and add the configuration key that you have received upon registration in the field below ( GDPR Consent Provider Key ) and bammm, all other platforms you are adding through this template will act keeping GDPR in mind. No cookies placed before consent has been accepted. Google Consent Mode is of course working, so you are still able to get data on your unconsented sessions and users.

Landing page experiments

One problem that CMPs have introduced is running A/B test aka web experiments on landing pages for first time visitors. The problem is that Experiment tools need to take a note of the user to provide a consistent experience, so thes need to place a cookie to know which experience to serve to the user. This of course cannot happen before the user accepts the utilization of cookies.

Unfortunately when the user accepts cookies the webpage is fully visible. If the Experiment platfrom started to rearrange content at this point then the user would see elements moving around the page, appearing and disappearing – which is not a great user experience. Something has to be done to allow the A/B testing tool to do its magic before the page is fully loaded and visile.

There is a simple tickbox within the ClientConscious template that adds support for landing page A/B testing for first time visitors.

You simply have to tick this box and all is done.

What is does under the hood, is that it performs a quick reload of the webpage after cookies are accepted that is pretty much not noticable by the user. This reload allows the Experiment platform the do its work upon the new page load before the page is fully visible.

Some other things that need some caution is keeping track of the original traaffic source, and avoiding double tracking the first page view, but these are of course also handled, and you don’t need to worry about these.