• by Gavin O'Malley  @mp_gavin, December 5, 2012

AOL’s Advertising.com unit late Tuesday announced the acquisition of ad-targeting and retargeting specialist Buysight. Terms of the deal were not disclosed, but Buysight -- formerly Permuto -- has raised about $16 million since its launch in 2008.

“We strongly believe that both brand and performance display as well as mobile and video campaigns benefit from dynamic, targeted creatives and messaging,” Ned Brody, CEO of AOL’s Advertising.com Group, said.

Specifically, Brody is counting on Buysight to improve AdLearn, Ad.com Group’s optimization engine.

Simply put, retargeting is the practice of serving consumers ads -- usually in the form of a banner -- for products or services based on content they have previously viewed online.

And retargeting has become big business. In September, Criteo, a New York-based retargeting startup, raised $40 million on an $800 million valuation. Also of note, Jason Kelly -- formerly of Google and AdMeld -- recently took the helm at Sociomantic Labs, a rapidly growing Berlin-based retargeting firm.

Also driving the retargeting business is its increasing cross-pollination with real-time bidding, which has made online ad-buying more efficient -- and by many measures, more effective.

The Ad.com Group includes Advertising.com, Adtech, the AOL On Network, goviral and Pictela.

AOL brought in Brody in May to implement what it called a more “segmented” operational strategy, which included aligning its operating focus around brand measurement and management.

Along with a continued focus on consumer brands, AOL has recently sought to scale its enterprise advertising and publishing brands with the Ad.com Group.