The 10th annual ranking includes brand, marketer, agency holding group, agency network, agency office and independent agency.
MullenLowe Lintas, Ogilvy India and Colenso BBDO land in the top five most effective agencies.
GLOBAL - WPP has topped the Effie Index as the most effective agency holding group globally for the fourth year in a row, as Omnicom's BBDO is named the most effective ad network.
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