Ms. Hall, 36, has been a reporter and editor at U.K. weekly trade magazines including Campaign and most recently wrote about the ad industry as a free-lancer for The Financial Times and other London newspapers.
"Emma impressed us with her knowledge and enthusiasm, as well as the high regard in which she is held by key people in our industry," said Scott Donaton, editor of Ad Age.
"London is the ad market outside the U.S. that most interests our readers and the source of European and other international news," Mr. Donaton said.
Ms. Hall will report on breaking news, trends and analysis, and contribute to Ad Age's weekly international page and special reports such as "Global Players" (April 7). She reports to International Editor Laurel Wentz in New York.
Ms. Hall can be reached in London at (44) 794 123 7761 or by e-mail at email@example.com.