After the buy out of Double Click google launched AdManager.

As part of our continuing commitment to provide publishers of all sizes with tools to improve revenue opportunities and productivity, we're excited to announce Google Ad Manager.

If you operate a site with remnant ad inventory as well as reserved ad inventory that you sell directly to advertisers, then Ad Manager is for you. It can help you sell, schedule, deliver, and measure directly-sold and network-based inventory. Google Ad Manager offers a wealth of features, including an intuitive user interface, automated yield optimization, and proven Google speed and reliability. Best of all, Google Ad Manager is free.
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