- Brian Morrissey

NEW YORK Tribal DDB worldwide CEO Paul Gunning (pictured) is taking over from U.S. CEO and global CMO Liz Ross, who is leaving the company.

Gunning and Ross said the decision to part was "mutual" and stemmed from Gunning's desire to have a more operationally focused leader in the U.S. dedicated to getting Tribal's four offices working more closely together and finding ways to streamline the unit's relationship with DDB.

"These are crazy times we're living in. Our clients are demanding, as they should, absolute maximum efficiency," Gunning said. "I think what's called for to be successful is someone who is focused on the operations of the offices, dealing with the nuts and bolts and moving pistons of this company in the United States."

Ross said she was not the right fit for a focus on cost savings and inter-office operations and making decisions such as whether only one location should have a center of excellence in a digital practice area.

"Where the company is going and what is required is just different than what I want," she said. "Where I was pushing and what I love doing -- which is growth and creative and big ideas -- was being superseded by this structural and operational bent. I didn't want to do that." Ross was in the midst of moving from her San Francisco base to Chicago.

The skake-up comes less than a year after Tribal lost its longtime worldwide CEO Matt Freeman, who left the agency to become CEO of ad network Go Fish, later renamed Betawave. Gunning, president of Tribal DDB East, was named Freeman's replacement. Ross, who led Tribal's operations in S.F., stepped up to become U.S. chief and take the global marketing role.

Tribal has also lost the ecd of its Dallas office, Thomas Tafuto, who has joined Digitas in New York as svp, creative.

Gunning said the agency is performing well and is currently in 20 new business pitches. It maintains good standing with top clients Clorox, McDonald's and Pepsi, he said.

Still, the tough economy will drive agencies back to basics, he said, focusing first and foremost on making sure they're delivering for existing clients. "I want to be very close to our existing clients and how we work with them on a daily basis," he said. "I don't want anything between me and them."