Named Most Effective Agency Network NEW YORK, June 5, 2024 /PRNewswire/ -- Effie Worldwide today announced the 2023 Effie Index, the annual ranking of the companies behind the world's most effective marketing, with McCann Worldgroup named the Most Effective Agency Network for 2023. McCann Worldgroup earned the top position with a strong performance across all regions in 2023. Contributing to McCann Worldgroup's Most Effective Agency Network global ranking were the following results: Regionally: #1 Agency Ne ...