From July 2010 to April 2014, Isikoff was the national investigative correspondent for NBC News. He resigned from NBC, citing the network's move in a direction that left him with "fewer opportunities" for his work. He had previously worked for "Newsweek", which he joined as an investigative correspondent in June 1994, and wrote extensively on the U.S. government's War on Terror, the Abu Ghraib torture and prisoner abuse, campaign finance and congressional ethics abuses, presidential politics and other national issues.