The hot topic involving the three million migrant workers in Beijing last week was a police order to apply for a new kind of document that will divide them into three categories. Those who have lived in Beijing for more than three years, hold a legal job and have no criminal record can apply for an A-class temporary residence permit. Those with a legal job, no criminal record and between one and three years of residence can apply for a B-class permit. A C-class permit will go to those who have been in Beijing for less than an year and those who collect rubbish and work in the sex, sauna and the entertainment business, however long they have been in the city. The permits, to be issued in the first half of the year, will replace the 'temporary residence permit' issued to all migrant workers - that is to say the ones who apply. Up to half do not apply, because they do not want to spend the 200-yuan fee or because they do not want authorities to know where they are. The police unit in charge of migrant workers which issued the order declined to comment on why it is introducing the system. 'It is probably due to the bid for the Olympics in 2008,' said Liu Mei, a waitress at a privately owned restaurant from the central province of Anhui who has lived in Beijing for 18 months. 'The authorities want to have better control of the migrant population. But it is hard to see how they will achieve this by having three kinds of document instead of just one, as now. 'The other explanation is that it is a form of squeeze. We pay 198 yuan a year for our one-year permit. For the A and B, the police can charge more.' Du Yingnan, from Shenyang, has lived in Beijing for more than three years and works as a designer at a magazine. 'The police round-ups began in the summer of last year. They arrested migrants who were not carrying three documents - an ID card, a work card and temporary residence permit,' he said. 'Those who did not have all three were taken to a giant sand pit in the suburbs where they worked for two or three weeks removing rocks and stones from sand for construction sites. If they could not produce the three documents, they were put on a train to their home place and their families made to pay the train ticket. 'I think the new documents are part of the Olympic bid. The authorities wanted to reduce the number of migrants and make the city prettier.' According to official figures, police last year rounded up 295,000 migrants without the proper documents and sent them home, after a period of compulsory labour. Mr Du said the police methods were excessive, with officers using guns and each station having a quota of arrests to meet. 'People speak of human rights, but this is a step back. Many migrants have no documents. They did not dare go home until after midnight,' he said. The police methods seem to have support among the public support, with most of the city's crime blamed on migrants and complain they make the traffic worse, fill the buses and subway trains and worsen conditions in an already overcrowded city. Despite this, the migrants do not attract the same resentment as in Shanghai or many other cities in the world. 'Beijing is a metropolis and attracts people from all over China,' said taxi driver Wang Hongguo. 'This is normal. The migrants bring money and business and create wealth. Besides, we Beijing people are lazy and are unwilling to do many of the jobs they do, even if we are out of work. It is a question of face. So we are grateful they do these dirty jobs.' That certainly is the official line. At a meeting on March 22, Meng Xuenong, the Beijing vice-mayor responsible for migrant workers, described them as 'a member of the large family of the capital'. 'They have entered into every segment of the city's life and created part of its wealth,' he said. Mr Meng said the aim of authorities was to do a better job of regulating the migrants. Their jobs range from the humblest to the highest. Some collect and process rubbish and clean the streets and toilets, while others design software programmes and investment plans in paperless offices. Those hired by technology companies can apply for the A-class permits immediately, without waiting for the three-year residence period. The migrants in Beijing are part of the army of 80 million people in China who have left their homes in search of work. It is one of the most dramatic signs of the change brought about by Deng Xiaoping and his reforms after 1978. For the 20 years before him, China had one of the most restrictive movement policies in the world. Mao Zedong suspended the right of Chinese in the 1954 constitution to live where they chose and ordered almost the entire population to live where they were born. It was both an economic necessity, since there were shortages of food, work and accommodation almost everywhere, and a way to keep people under control. Under an order passed by the State Council in 1960, only three people in every 2,000 were allowed to change their place of residence each year - rural people who went to university or were officers demobilised from the army.