AT&T announced today that chairman and CEO Ed Whitacre will retire in early June, with COO Randall Stephenson as his successor. Whitacre, the longest-running telecom top exec, became CEO of what was then Southwestern Bell—the smallest of the Baby Bells—in 1990, transforming the company ithrough a series of acquisitions and mergers into what AT&T calls the “the world’s largest communications company.” Stephenson is credited for integrating the companies in what the new AT&T. Within weeks of his promotion, he’ll have to deal with what is at once one of the company’s greatest marketing coups and challenges—the exclusive launch of Apple’s iPhone. Release.

Staci adds: Whitacre’s retirement package has been super-sized, too. His payout is $158.6 million, including deferred income. WaPo is among those with the details. He could add another $106 million or so in shares that haven’t vested; he also gets three years at $1 million per for consulting.