As U.S.-based advertisers continue to expand globally, interactive agencies have had to shore up their regional hubs and cross-border communications, and follow the "think globally, act locally" approach, writes ClickZ (via MediaBuyerPlanner). Carat International, for one, manages its global campaigns from its London headquarters and offices in Paris, Hong Kong, and Wiesbaden - coordinating the execution of each campaign with local offices in some 75 countries.

Overall marketing strategy shouldn't change in different markets, but execution can vary dramatically. "The global hubs are here to make sure the overall strategy is consistent," mOne's Global brand team head in North America, Suhaila Suhimi-Waldner, told ClickZ. mOne tends to focus its media spend in the top seven regions where a client's sales take place: usually, major European regions, China, Russia and India.

Creative agencies face global campaign challenges, as well. Communications and logistics are among the biggest obstacles, says Marcelo Guerra, account director at Organic. Everyone involved needs to understand not only the central message, but the importance of tailoring it to the needs of each local market, according to Guerra.