Subtitles section Play video Print subtitles Hi, I’m David Baker. I’m the head of ads policy engineering at Google. We have a vested interest in creating the least intrusive and best ad experience for our users. That means showing you the right ads when you want them, and doing our best to never show you ads that can be harmful. That’s why our ads engineering efforts are so focussed on protecting the user. This is a very difficult challenge given the number of ads online, and there are a lot of malicious players. We’ve dedicated tens of millions of dollars and hundreds of engineers and policy experts to building systems and tools to detect violations of our policies. And when we find a scam, we don’t just ban one ad, we ban the advertiser from ever working with Google again. In 2011 out of the billions of ads that were submitted to us, we shut down about 800,000 advertisers and more than 130 million ads for violating our policies. But how do we find them? Our first defense is automated systems that proactively catch scams by monitoring the content of each ad and scanning the advertiser’s website before the ad is ever shown. When we detect a threat, our systems automatically seeks out and find similar websites and scams, immediately broadening our reach. And quite often, our experts personally review complex or suspicious ads that our software has flagged, but which needed a real person to make a decision. Advertisers, users and other authorities can report scams directly to our policy department, and we’ll respond as quickly as possible. We’re committed to developing the best experience for our users and remain committed to earning your invaluable trust.