YouTube has paused all its TrueView discovery ads in order to implement changes to the way they work. TrueView discovery ads show as related videos and in the mobile search results, and are expected to be offline until the end of June 2017. The need to change the current set up comes after many major UK and US advertisers left the site, after it became apparent that big brands were appearing next to highly contentious content. In response, Google has said that “new brand safety measures” were being applied to YouTube, adding that it was also making changes to ad targeting which would take into account a user's search history. One of the changes includes channels undergoing a brand safety check before they can be accepted into the YouTube Partner Programme to show adverts.