Noble Corp., a $2.8 billion offshore drilling contractor, appointed James MacLennan CFO, controller and senior vice president. He replaces Dennis Lubojacky, who served as interim principal finance and accounting officer since CFO Thomas Mitchell left in September. MacLennan, 52, joins the Swiss company from Ennis Traffic Safety Solutions, where he was CFO and corporate secretary. Earlier, he served as CFO at hotel owner and operator Lodgian, medical device manufacturer Theragenics Corp. and technical products company Lanier Worldwide.

The Navigators Group, a $777 million New York City-based insurance holding company, named Ciro DeFalco CFO and senior vice president. He succeeds Francis McDonnell, who retired. DeFalco, 56, served as interim CFO at Navigators since October. He joined the company in September from White Mountains Re Group, where he was senior vice president and group planning officer. Previously, DeFalco held a variety of finance positions in the insurance industry.

NCI, an information technology company with $581 million in 2010 revenue, appointed Lucas Narel CFO, treasurer and executive vice president. He replaces Brian Clark, who was named president of the Reston, Va., company. Narel, 37, joins NCI from CGI Federal, where he was vice president of finance. Earlier, he was vice president and corporate controller for Stanley, a company that CGI acquired in 2010.