In a country where dissidents are often detained, a single episode of intimidation may seem depressingly routine. But not every country is preparing to host the Summer Olympics, and not every activist has won a prestigious international award. Alexandra Li in Beijing explains what the imprisonment of Chen Guangcheng, and the recent harassment experienced by his wife Yuan Weijing, have to do with the 2008 Games.

At eleven o'clock last Thursday night, Yuan Weijing received an ominous phone call. The caller identified herself as a member of the foreign affairs office from Yuan's home village near Linyi city in Shandong province. "Since last year, your passport has been declared invalid, the reason being that you've been implicated in a criminal offense," said the caller, who went on to advise Yuan not to try to travel overseas the next day.