wpp_logo.gifWPP Chief Executive Martin Sorrell says that the ad industry will never be the same.

While most ad execs are in agreement that the worst is over, nobody knows when things will really bounce back. Clients have gotten used to paying less, reports the Wall Street Journal, and the pressure is still on to keep prices low.

“There is no one in the industry whose clients haven’t said, ‘We are under pressure, so you have to cut fees,”‘ David Sable, vice chairman and chief operating officer of Wunderman, a direct-marketing firm owned by WPP, said recently. Some marketers have even slashed prices retroactively, meaning that they’re getting paid less for work they already completed.

Yesterday WPP reported a 48% drop in first-half profit to $177.3 million.