The news that the former NBA player Stephen Marbury has been granted China's permanent residence permit, also known as the Chinese green card, has once again aroused people's interest in this issue.It is reported that Marbury, who has led the Beijing ducks to three Chinese Basketball Association championships, fell into the category of "outstanding contributors" to China. Most people have heard of the permanent residence permit for foreigners living in China, but rarely have they met anyone who actually holds it.Indeed, in the first eight years following the launch of the scheme in 2004, only about 5000 foreigners out of the 600,000 who lived in China were granted this permit.So what is this mysterious residence permit, and what qualifications do foreigners have to meet in order to get it? PIK speaks with Liu Guofu, professor of law at the Beijing Institute of Technology. Professor Liu's recent research focuses on immigration law; David Moser, an American who first came to Beijing in 1986 and has lived in China continuously since 1994; and Wang Huiyao, president of the Center for China and Globalization, a think tank based in Beijing.