China's estimated 94 million migrant workers are owed as much as RMB 100 billion (US$12 billion) in unpaid wages, according to government trade union figures.
Up to 70 percent of the unpaid wages are in the building industry, with a large proportion of the remainder in the service industry, especially restaurant and food businesses.
Fearing the potential for major social unrest the government issued regulations and laws in 2003 calling for migrant workers to be treated fairly and paid on time.
According to the government, there are some 207 million workers in China, of which 94 million are surplus rural laborers seeking work in cities.