In the early 1970s, Dolan founded Home Box Office, the first premium programming Service in the cable television industry, which he sold to Time Life. Later he organized Cablevision Systems Corporation on Long Island and has spearheaded many of the company's advancements. Most recently, he was the vision behind VOOM, Cablevision's effort to expand content delivery and meet the demands of the exploding HDTV market, which was expected to include 6 million households by the end of 2003—and 12 million by year-end 2005.