CBS has made the transition atop its reality department official by promoting Chris Castallo to EVP Alternative Programming. Castallo previously served as SVP and a strong No. 2 to former department head Jennifer Bresnan, who earlier today announced her departure to relocate to New York. Castallo will oversee all non-scripted series programming for CBS, reporting to CBS Entertainment president Nina Tassler. That includes development of new reality, game shows and other non-scripted programming and oversight of CBS’ current slate of reality series including Survivor, The Amazing Race, Big Brother and Undercover Boss. “Chris is a skilled executive who thinks like a programmer, producer and promoter all at once,” Tassler said. “He’s a terrific combination of a hands-on executive with a great vision for the genre, and we look forward to his leadership in this area.”

Castallo has been at CBS since 2007, working closely with Bresnan. He joined CBS from NBC, where he was SVP Drama Development, overseeing development and production of such series as Heroes, Studio 60 and Kidnapped. Previously, he was SVP at Tollin/Robbins Prods, where he was involved in the development and production of Smallville, One Tree Hill and What I Like About You.

CBS is the second broadcast networks to be changing alternative heads in what are challenging times for broadcast unscripted programming. That fare has largely struggled to produce a new hit the past couple of years (since Undercover Boss and NBC’s The Voice), while cable networks have had a field day with mega hits like Jersey Shore and Duck Dynasty. Mike Darnell exited from Fox in May, with the search for his replacement still underway but expected to conclude within a month.