Cablevision Systems Corp. has appointed company veteran Brian G. Sweeney to be president. CEO James L. Dolan had been president since 1998 and has been chief executive since 1995. Sweeney, 49, has worked at Cablevision for more than 20 years, the Bethpage-based company said Wednesday. Previously, he was senior executive vice president, strategy, and chief of staff to the CEO. He will work with Dolan on the company's long-term direction, day-to-day operations and oversee its local media properties, including Newsday and News 12 Networks.

Cablevision said Kristin A. Dolan, 48, has been appointed chief operating officer. She has worked for the company for 24 years and previously served as president of the company's Optimum Services. In her new role, she will lead all aspects of cable operations.