The first time the men with clipboards came, Li Yuexian told them he had one daughter, an 11-year-old tomboy who plays a mean game of badminton. The second time they came, he admitted to having another, a pudgy seven-year-old girl who doesn't like sports at all. But the third time they came, the 43-year-old garbage collector did not mention his third child, a four-year-old with pigtails and a gap-toothed grin. They told me they wouldn't punish me as long as I filled the form out honestly, he says, sitting in his musty, two-room shack in Beijing. But it's hard to believe them.Across China last week, 6 million men and women with clipboards fanned out in jeeps, on bicycles and even on camelback in hopes of counting every last citizen of the world's most populous nation. Their census results will influence everything from China's education budget to water allocation. But the reluctance of millions like Li to answer forthrightly could drastically skew the data. Even a miscalculation of 2% could result in an uncounted 26 million people, roughly equivalent to the population of Scandinavia. Counting one-fifth of the world's population puts a lot of weight on our shoulders, says Liu Jianwei, deputy director of the Beijing census administrative office. If we miss people, they lose the chance of government protection. Two groups are particularly eager to avoid the census takers: migrant workers, who usually lack permits to live in their new cities, and so-called black children, who were born in violation of China's one-child policy. Garbage collector Li has both problems. Eight years ago, he moved from his native Hebei province to Beijing with his seamstress wife and eldest daughter. The couple settled in a sprawling slum on the outskirts of the capital and promptly had two more girls. Life in Beijing is much better than back in rural Hebei, says Li: his wages cover the family's rent, tuition for the underground school for migrant children that his kids attend, as well as the odd night of karaoke. But officially, Li and his family don't belong in Beijing, and he could be hit with a hefty fine if officials took notice of them. Authorities insist that the answers given to census questions will not be used against anyone; they promise to burn the forms after the data is entered into a computer. But many fear that greedy local officials will be tempted to peek at the information and use it to extort money from those who have violated the law. There is so much corruption in China, says a clothing vendor who gives his name as Zhao. The census is another opportunity for officials to take advantage of the common people.Not reporting themselves, though, could cause illegals even more trouble. Up to 125 million migrant workers and 80 million unregistered children may have eluded census takers a decade ago, when the last national count was conducted. As farmland ceases to support the nation's peasants and bankrupt state-owned enterprises lay off millions of workers, whole villages are moving to start anew in China's teeming cities. Flying under the radar of the authorities leaves these millions at the mercy of unscrupulous factory owners and others, who can withhold wages or evict them without fear of repercussions. The government needs to protect these people, says a Beijing labor advocate. Otherwise, it could eventually face a revolt by millions of dissatisfied laborers it didn't even know existed.Yet even some among China's Elite are loathe to answer the census form honestly. For the first time, some of those polled are being asked questions about their daily life: whether they drink tap water, what cooking fuel they use and what materials were utilized to construct their homes. They are required to detail whether they own a flush toilet or water heater and how much money they spent on buying a home—a capitalist notion unthinkable just a decade ago. Such questions may help the Ministry of Construction better meet China's housing needs, but they alarm a generation wary of the pervasive inquisitiveness of the Communist Party. Why should I tell the government whether my house has a bathroom or not? asks computer programmer Liu Wenfang. Are they going to tax me for having a bathroom? For garbage collector Li, telling the truth is even more problematic. The census taker who knocked on his door for the third time last week is also in charge of the neighborhood's family-planning committee. When the initial results of the census are released next February, Li's pigtailed third child won't be counted. Nor, he says, with a wink, will his fourth and last child, a long-awaited son born just four weeks ago.