Baton Rouge-based outdoor advertising giant Lamar Advertising Co. has acquired Alliance Airport Advertising for an undisclosed sum.

The deal adds advertising and displays in McCarran International Airport in Las Vegas; Phoenix Sky Harbor International Airport; Salt Lake City International Airport; Portland (Oregon) International Airport; and Bob Hope Airport in Burbank, California. With the transaction, Lamar now operates advertising concessions at a dozen airports that serve more than 125 million passengers annually.

“As we’ve gotten to know the airport advertising business over the last several years, we have recognized that it’s a terrific fit within Lamar,” Chief Executive Sean Reilly said. “Alliance has established powerful relationships with some of the nation’s leading airports, and we look forward to extending their proven operating model to additional airports.”

Shauna Forsythe, who founded Alliance 16 years ago and served as its president and chief executive, will lead Lamar’s airport division. The new division will be called Lamar Alliance Airport Advertising.