Chance Patterson, VP of international communications for Discovery Communications, has been cast in the top PR slot at Harpo Studios, the production juggernaut of Oprah Winfrey.

Patterson fills a post being vacated by Lisa Halliday, a 12-year veteran who is leaving the company and moving back to Los Angeles from Harpo’s Chicago base.

Patterson takes the title of senior VP, corporate affairs and communications, Harpo Studios. He’ll report to Sheri Salata and Erik Logan, presidents of Harpo and OWN: Oprah Winfrey Network.

A lawyer, Patterson led communications for Discovery Networks International, which is in 200 countries. He previously led corporate communications and government affairs for Sirius XM Radio, including during the XM/Sirius merger.

Earlier stints included KPMG (gov’t relations) and law posts with Tucker Flyer & Lewis and Calfee Halter & Griswold.

In addition to Winfrey's branded empire, Harpo developed "Dr. Phil," "Rachael Ray," "The Dr. Oz Show," and "The Nate Berkus Show," among other projects.

Halliday is stepping down after 12 years to "pursue other interests" in LA., she said in a statement to O’Dwyer’s earlier this week. She joined Harpo from The Walt Disney Company’s Buena Vista Pictures Marketing unit in 1999.