Yet despite the "encouraging" results and a positive outlook for the rest of the year, WPP chief executive Sir Martin Sorrell believes brands remain cautious when it comes to ad spend and are heavily focused on cost-cutting. "Procurement and finance remain the dominant functions for understandable reasons, with marketing taking a back seat," he says, adding that many of WPP's clients, which include Samsung, Nestle and Universal Music Group, are facing new challenges, leading to "considerable pressure in the system" and a short-term focus on results. "If you are running a legacy business, as many of our clients are, you face disrupters like Uber and Airbnb at one end of the spectrum, zero-based cost budgeters like 3G and Coty at the other end, with seemingly short-term focused activist investors in the middle, like Nelson Peltz, Bill Ackman and Dan Loeb. There is, therefore, considerable pressure in the system," he explains.