-By Kenneth Hein

Wendy Clark, a prime force behind the rebranding of AT&T, is stepping down as svp-marketing for the telecom giant.

A statement issued by the company said it is beginning a search for her replacement: "The AT&T brand is iconic in the communications industry globally and the company is one of nation's largest advertisers. We plan to conduct an extensive search for candidates to lead AT&T's advertising and brand management efforts as the company continues to expand, domestically and globally."

Like Clark, the new svp will report to Cathy Coughlin, AT&T senior executive vice president and global marketing officer. Clark's last day was not known.

Sources said that Clark wasn't interested in relocating. AT&T is relocating its headquarters from San Antonio, Texas, to Dallas.

A former svp/director of client service at GSD&M, Austin, Texas, Clark joined AT&T in 2004. Shortly afterward she was charged with rebranding the company, formerly known as SBC, which changed its name to AT&T in 2005 after it bought the former "Ma Bell," capping off several mergers and acquisitions. AT&T also bought Cingular Wireless and, in a somewhat controversial move, rebranded it as AT&T as well.has

At the ANA Confab last October, Clark said, "After the [nine] mergers, we knew we had to evolve ourselves." The new AT&T received a huge boost from its association with Apple's iPhone, which Clark called "a steroid for our rebranding."

AT&T was the biggest spending brand of measured media in 2007. It spent $1.86 billion (not including online), per Nielsen Monitor-Plus. BBDO, New York, is AT&T's agency.

"We appreciate Wendy Clark's leadership during a period when the company significantly expanded its operations and successfully launched the new AT&T brand. We wish her all the best in the future," said the company's statement.