In a surprise move, former New York City Mayor Rudolph Giuliani and ex-prosecutor Marc Mukasey are leaving Bracewell & Giuliani to join Greenberg Traurig. The 71-year-old Giuliani will chair the firm’s cybersecurity and crisis management practice and serve as a senior adviser to Greenberg Traurig executive chairman Richard Rosenbaum. Mukasey, 48, will co-chair the firm’s white-collar defense practice.

Giuliani, a former U.S. attorney for the Southern District of New York, joined Houston-based Bracewell in 2005, shortly before he began his unsuccessful run to be the Republican U.S. presidential nominee. To accommodate Giuliani, the firm changed its name from Bracewell & Patterson and took out a $25 million loan to open a New York office. The firm at the time also agreed to pay $10 million for the services of Giuliani Partners, a consulting firm that Giuliani still heads.