Faced with a fall in tourist numbers due to the financial crisis and a reputation for unfriendliness, the Paris tourist board has made a simple request to the city's residents: smile.
Visitors to Paris, the world's most visited city, have fallen 17 percent since January compared with the same period in 2008, official figures show.
To counter the slump and boost revenues, the tourist board has set up stands manned by teams of "smile ambassadors" to welcome holiday makers at the city's most popular spots.
As if to heed its call, hundreds of roller-skaters formed a giant smile in Place Vendome in the city center on Sunday.
"We have to work on striking and simple images. There's nothing as telling as a smile," said Paul Roll, who heads the tourist board.
In May, a questionnaire carried out by travel site TripAdvisor found Paris to be the most over-rated city in Europe, citing its high prices and unpleasant residents.
Daniel Fasquelle, founder of a tourism association, said that French from all walks of life needed to play their part.
"If we want tourism, which has generated more than 2 million jobs, to remain a major economic sector, everyone has to get behind it — professionals, elected representatives and French people," he said.
"It's the American tourist lost in Paris that we inform politely, it's the English person looking for the way in northern France who we don't get impatient with by honking our car horns," he said.
Paris is doing more than trying to make its residents smile to draw in more visitors.
It is now possible to enjoy a virtual visit of the Champs-Elysees, the so-called "most beautiful avenue in the world," on the Web site ChampsElysees.org.
Plans for a string of new luxury hotels are also in the pipeline, and Secretary of State for Tourism, Herve Novelli, is counting on a cut in taxes for the restaurant industry, which came into force on July 1, to boost tourism.