Longtime HBO producer John Hoffman has signed on to head documentary and specials for Discovery Channel.

Hoffman’s appointment as exec VP of documentaries and specials marks another high-level exec move by Rich Ross, who formally took the reins as Discovery prexy this week.

Ross, formerly of Shine America and Disney, will make his first appearance as Discovery topper today during the Discovery Communications portion of the winter Television Critics Assn. press tour in Pasadena, Calif.

“John is one of the best in our business, and his filmmaking experience, coupled with his ability to bring together unprecedented partnerships, will keep Discovery moving forward as leaders in groundbreaking and award-winning documentary films,” Ross said.

Hoffman most recently served as CEO of non-profit production venture the Public Good Projects, which produced the docu “Sleepless in America” that aired on National Geographic Channel last year. During his 17-year run at HBO’s documentary arm, Hoffman steered such noted projects as “The Weight of the Nation,” “The Alzheimer’s Project,” “Addiction,” “Last Letters Home: Voices of American Troops From the Battlefields of Iraq” and “In Memoriam: New York City, 9/11/01.”

On Wednesday, Ross announced the appointment of producer John Goldwyn as exec producer overseeing Discovery’s expansion of scripted programming.